Can We Achieve .99c for Interstellar Travel?

AI Thread Summary
Achieving 0.99c for interstellar travel is theoretically possible but would require significant technological advancements that are not currently on the horizon. Concepts like Bussard scramjets and various propulsion methods (beamed propulsion, matter/antimatter reactions) face substantial feasibility challenges, with many deemed impractical for manned missions. Time dilation would result in long travel times from the crew's perspective, taking thousands of years to cross the galaxy. Establishing a galactic civilization would necessitate not just advanced technology but also stable ecological and social systems aboard the spacecraft. Overall, while the idea of near-light-speed travel sparks interest, practical implementation remains far from realization.
cjackson
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Is it possible to build a vehicle that can accelerate to .99 C?

How would we go about doing something like this?

If at all possible, how many centuries or millennia is it before this can be accomplished?

Could a Bussard scramjet do it?

How large would a laser/maser/gaser have to be to get the craft up to such speed?

How long would it take from the crew's perspective to cross the galaxy?

How big would the craft be? I imagine a lot of fuel would be required even if you could gather propellant along the way - Bussard scramjet. What kind of fuel would be needed?

Would such a vessel help establish a galactic civilization? Or would time dilation make implausible?

What would it look like?

Are any sort of warp drives completely impossible? If so, which of the following would best for interstellar travel: beamed propulsion, matter/antimatter reaction, Bussard scramjet, or something else?
 
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cjackson said:
Is it possible to build a vehicle that can accelerate to .99 C?

Theoretically yes.
cjackson said:
How would we go about doing something like this?

No time soon, it would require fantastic advances in technology that don't look to be anywhere on the drawing board.
cjackson said:
If at all possible, how many centuries or millennia is it before this can be accomplished?

Same answer as above.
cjackson said:
Could a Bussard scramjet do it?

I take it you mean "ramjet" and no, http://en.wikipedia.org/wiki/Bussard_ramjet#Discussions_of_feasibility".
cjackson said:
How large would a laser/maser/gaser have to be to get the craft up to such speed?

http://en.wikipedia.org/wiki/Beam-powered_propulsion" .
cjackson said:
How long would it take from the crew's perspective to cross the galaxy?

At .99c time dilation is 0.07 minutes for every minute for an observer at rest. To cross from Earth to the far side of the galaxy (~70kly) would take 4962.168 years from the perspective of the crew. From one side of the galaxy to the other (~100kly) would take 7088.821 years.
cjackson said:
How big would the craft be? I imagine a lot of fuel would be required even if you could gather propellant along the way - Bussard scramjet. What kind of fuel would be needed?

That question can't be answered because it depends on technologies that haven't been invented yet e.g. how much mass do you need to hold the necessary stable ecology, industry and society. As linked above ramjets would not work.
cjackson said:
Would such a vessel help establish a galactic civilization? Or would time dilation make implausible?

In addition to such a vessel you would also need to be able to terraform otherwise you're not going to have a civilisation. Whether or not it could work as a civilisation is anyone's guess, see the http://en.wikipedia.org/wiki/Fermi_paradox" for further discussion.
cjackson said:
What would it look like?

The ship or civilisation? Either question is as unanswerable as a Neanderthal trying to envision Facebook.
cjackson said:
Are any sort of warp drives completely impossible?

On the subject of warp drives http://arxiv.org/PS_cache/gr-qc/pdf/9905/9905084v5.pdf" . The "trick" is to change the warp bubble so that it's exterior radius is microscopic yet the interior radius is large enough to accommodate your vehicle (essentially making a warp bubble that's bigger on the inside than on the out). Apparently this would greatly shrink the amount of energy needed to manageable levels. They don't outline how exactly a shell could be build around a ship in such a fashion nor how the ship could leave.

However neither of these approaches fixes the other problems of a warp bubble such as requiring the construction of an exotic matter shell, superluminal signalling to steer/control the bubble and the huge amount of radiation a warp drive subjects you to. There are some interesting (but technical) objections in http://arxiv.org/PS_cache/gr-qc/pdf/0406/0406083v2.pdf" that apparently show that a warp drive would only be capable of very low velocities as well as highlighting other problems.

In summary unless you have a way of making speculative impossible exotic matter, it's not going to happen (and might not even if you could).
cjackson said:
If so, which of the following would best for interstellar travel: beamed propulsion, matter/antimatter reaction, Bussard scramjet, or something else?

None of them. For manned interstellar travel beamed propulsion won't be strong enough, M/Am rockets are far too dangerous (your "vessel" is a weapon so powerful that it could easily annihilate the entire surface of Earth countless times over) and the Bussard ramjet won't work.
 
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wow ok a lot of questions about 1 thing. First I think its theoretically possible I guess. If we were to have a ship that ran on our current fuel and managed to build it, it would probably take a thousand years to even get to 99%C and also an almost infinite amount of energy. Space is huge. It would take many generations of people to travel even to the closest stars. If we ever discover a wormhole (or if they even exist), that would be a much better bet. ^ I agree with the warp bubble and have heard stuff about it, but who knows exactly how much faster that would be.
 
CosmicEye said:
wow ok a lot of questions about 1 thing. First I think its theoretically possible I guess.

It's theoretically possible but that doesn't mean much. It's theoretically possible to rearrange every star in the galaxy, doesn't mean we'll ever have the knowledge, resources and will to do it.
CosmicEye said:
It would take many generations of people to travel even to the closest stars.

If you want people to survive you also have to be able to build:
  • A stable ecology
  • An industry capable of building and recycling nearly everything
  • A social, legal, political and economical model that allows the society on the ship to survive harmoniously for thousands of years
All of these are extremely http://en.wikipedia.org/wiki/Nontrivial" .
CosmicEye said:
If we ever discover a wormhole (or if they even exist), that would be a much better bet. ^ I agree with the warp bubble and have heard stuff about it, but who knows exactly how much faster that would be.

Wormholes suffer from the same problem as warp drives, they require probably impossible http://en.wikipedia.org/wiki/Exotic_matter" .
 
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Please don't forget that, as you get close to the speed of light, tiny specks of the interstellar medium will impact your ship with the kinetic energy of 20 megaton bombs.
 
skippy1729 said:
Please don't forget that, as you get close to the speed of light, tiny specks of the interstellar medium will impact your ship with the kinetic energy of 20 megaton bombs.

Doesn't this violate relativity? It seems to imply that certain speeds are the universal norm, and others are inherently fast. I thought the universe was supposed to look the same from any vantage point.
 
Algr said:
Doesn't this violate relativity? It seems to imply that certain speeds are the universal norm, and others are inherently fast. I thought the universe was supposed to look the same from any vantage point.

It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.
 
If you started out from Earth using an ion drive that slowly increased acceleration given enough time it would reach .99c.

You have to also remember time dilation and length contraction for the ship would mean by the time say it arrived at Proxima Centauri it would of aged differently and moved through a shorter space than it would appear to you as an observer who is relatively stationary on Earth.
 
Galron said:
If you started out from Earth using an ion drive that slowly increased acceleration given enough time it would reach .99c.

It wouldn't matter if it increased its acceleration, it just needs to have a constant acceleration but there are problems with this:

A) Supplying it with enough fuel to get to 0.99c - taking a http://en.wikipedia.org/wiki/VASIMR" as the best speculative ion drive with a specific impulse of 30,000 seconds you would need ~1000 parts kg fuel for every 1kg of ship

B) Having enough thrust to reach 0.99c in a reasonable time - taking VASIMR again if we assume a 1 tonne ship with 1000 tonnes of fuel then with a thrust of http://en.wikipedia.org/wiki/Ion_thruster#Comparisons" the ship will be capable of an average acceleration of 1e-6 and would reach 0.99c in roughly a million years.

C) All the other engineering issues of energy, waste heat etc

Galron said:
You have to also remember time dilation and length contraction for the ship would mean by the time say it arrived at Proxima Centauri it would of aged differently and moved through a shorter space than it would appear to you as an observer who is relatively stationary on Earth.

What do you mean move through a shorter space? From all reference frames the ship would have traveled the same distance.
 
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  • #10
ryan_m_b said:
It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.

This isn't quite true. Each would perceive time for the other running slow, while the ship is in motion. What is true is that when the ship is co-moving again with typical stars again, it will have aged less, and the rocket and a nearby planetary observer agree on this. A good terminology for this is time dilation (relative) versus differential aging (invariant).
 
  • #11
PAllen said:
This isn't quite true. Each would perceive time for the other running slow, while the ship is in motion. What is true is that when the ship is co-moving again with typical stars again, it will have aged less, and the rocket and a nearby planetary observer agree on this.

Yeah I get this, what was wrong with my explanation? (Not criticising, genuinely interested).
 
  • #12
ryan_m_b said:
Yeah I get this, what was wrong with my explanation? (Not criticising, genuinely interested).

You said: "However only one of them is experiencing time dilation ". That is misleading.

Also, it is, in fact true, that:

- while moving, the ship perceives the distance to a star as much smaller than appeared before they were up to speed (length contraction; which is why they still measure light from the star as moving at c: shorter distance, smaller elapsed time, compared to Earth bound measurement of lightspeed from the star).

- If you introduce a concept of odometer, there is a perfect symmetry between length and time. Time dilation is relative and once to equivalent clocks are comoving, their rates are the same, but their accumulated time reflects their path through spacetime. Similarly, length contraction is relative, but an odometer measuring integral of apparent distance traveled will be remain different and dependent on path through spacetime. The rocket will perceive it never traveled faster than c, and that it traveled 10 light years in one year because its odometer says it really only traveled e.g. .9 light years.
 
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  • #13
PAllen said:
You said: "However only one of them is experiencing time dilation ". That is misleading.

I see, of course. I should have explained my point more. Thanks.
 
  • #14
ryan_m_b said:
It is. From the perspective of the guy on the ship the speck is traveling at 0.99c, the speck sees the ship doing the same. The energy is the result of the kinetic energy that would be the same regardless of who was traveling at that speed.

However only one of them is experiencing time dilation because one of them has been in an accelerating reference frame and the other in an inertial.

I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"
 
  • #15
Algr said:
I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"

I don't really see why. The energy has nothing to do with time dilation or relativity, it's simply kinetic energy.
 
  • #16
Algr said:
I wasn't talking about the time dilation, but the "20 megaton bombs." At one speed you get hit by them, and at another you don't. This seems to me to point to a "proper speed of the universe"

No, ryan_m_b is completely correct. Speck says rocket moving very fast, hits hard; rocket says speck moving very fast, hits hard.

There is, of course, a frame for any region of space such that the total momentum of matter is zero, and one may describe speed in that frame as speed relative to average matter of the region. However, that is completely irrelevant to the principle of relativity.
 
  • #17
So there are no galaxies headed for Earth at 99% the speed of light? And no particles? It would only be space ships?
 
  • #18
Algr said:
So there are no galaxies headed for Earth at 99% the speed of light? And no particles? It would only be space ships?

Most likely, it will be nothing ever.

[Edit: missed the reference to particles. Particles hit Earth every day with .9999999c. They are called cosmic rays. Occasionally, they are so energetic that one proton carries as much KE as a thrown baseball.

If a 1 gram object had the speed of the fastest cosmic rays, it would hit Earth with an energy of about 1 hundred million gigatons of TNT
]
 
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  • #19
PAllen said:
[Edit: missed the reference to particles. Particles hit Earth every day with .9999999c. They are called cosmic rays. Occasionally, they are so energetic that one proton carries as much KE as a thrown baseball.

If a 1 gram object had the speed of the fastest cosmic rays, it would hit Earth with an energy of about 1 hundred million gigatons of TNT
]
For Q1 and Q2 below, imagine two objects traveling on a perfect head-to-head collision course.

Q1. Is it possible to calculate the energy released if two 1,0 gram objects, each traveling with the speed of the fastest cosmic rays, would hit each other?

Q2. What would happened if two 1 gram objects, one traveling with the speed of .9999999c and the other at 1c, would colide with each other? Is it possible to calculate the released energy in this impact?

Thanks :)
 
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  • #20
Lucutus said:
For Q1 and Q2 below, imagine two objects traveling on a perfect head-to-head collision course.

Q1. Is it possible to calculate the energy released if two 1,0 gram objects, each traveling with the speed of the fastest cosmic rays, would hit each other?

Q2. What would happened if two 1 gram objects, one traveling with the speed of .9999999c and the other at 1c, would colide with each other? Is it possible to calculate the released energy in this impact?

Thanks :)

I'm pretty sure (but not absolutely sure) you could just calculate the energy by each and add it up. So;

1 gram object traveling at 0.9999999c (299792428m/sec) would release 44,937,749,943,067.6 joules of energy or ~45 petajoules. So the collision of two grams would be ~90 petajoules
 
  • #21
ryan_m_b said:
I'm pretty sure (but not absolutely sure) you could just calculate the energy by each and add it up. So;

1 gram object traveling at 0.9999999c (299792428m/sec) would release 44,937,749,943,067.6 joules of energy or ~45 petajoules. So the collision of two grams would be ~90 petajoules

I used a joule to kiloton converter on the internet, if this converter is true the combined force would be about 21,48 kilotons.What about Q2? Is it possible to calculate the energy if one of the two one gram objects were traveling at 1c, and the other 1 gram object were traveling at 0,999999c?

And, finally, my Q3 =)
Is it possible to calculate the energy of a collision if both 1 grams objects were traveling at 1c?

I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

Best regards
Mattias
 
  • #22
I know that your goal is speed; but what about slow and steady?
What if Helium 3 could be used as a fuel source, and plotting courses to moons with robotic mining missions that would set up robotic mining colonies - no humans. These "colonies" would be the galaxtic "gas stations" for future missions when technology has caught up to speed (pardon the pun) to possibly carry humans :)
 
  • #23
Lucutus said:
I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

Best regards
Mattias

It takes infinite energy to accelerate an object with mass to c.
Maximilan said:
I know that your goal is speed; but what about slow and steady?
What if Helium 3 could be used as a fuel source, and plotting courses to moons with robotic mining missions that would set up robotic mining colonies - no humans. These "colonies" would be the galaxtic "gas stations" for future missions when technology has caught up to speed (pardon the pun) to possibly carry humans :)

You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.
 
  • #24
ryan_m_b said:
You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.

LOL .. yeah, I was trying to blend in so I could ask a Sci-Fi question :)

But nations are seriously considering this in the near future: http://www.explainingthefuture.com/helium3.html
 
  • #25
Maximilan said:
LOL .. yeah, I was trying to blend in so I could ask a Sci-Fi question :)

But nations are seriously considering this in the near future: http://www.explainingthefuture.com/helium3.html

Lol, first show me working fusion on the ground, then show me a working http://en.wikipedia.org/wiki/Fusion_power#D-3He_fuel_cycle", then show me a nuclear fusion propulsion system. After all of that let's examine the geopolitical, socioeconomic and scientific/technological situation at that point in history and then we can have a meaningful discussion about He3 mining.

I don't mean to sound flippant but discussing the role of He3 mining in future space exploration is not just putting the cart before the horse its putting the cart before the wheel.
 
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  • #26
ryan_m_b said:
Lol, first show me working fusion on the ground, then show me a working http://en.wikipedia.org/wiki/Fusion_power#D-3He_fuel_cycle", then show me a nuclear fusion propulsion system. After all of that let's examine the geopolitical, socioeconomic and scientific/technological situation at that point in history and then we can have a meaningful discussion about He3 mining.

I don't mean to sound flippant but discussing the role of He3 mining in future space exploration is not just putting the cart before the horse its putting the cart before the wheel.

http://fti.neep.wisc.edu/pdf/wcsar9304-1.pdf

http://www.lpi.usra.edu/decadal/leag/DecadalHelium3.pdf

Prototype Reactor:
"A commercial fusion reactor has never been built, but a prototype called the International Thermonuclear Experimental Reactor (ITER) has just begun construction in Cadarache, France. The plan is to generate the needed 100 million degree plasma by the year 2016, but a power plant that can supply electricity might not come online for another 20 years after that." reported by msnbc.com http://www.msnbc.msn.com/id/2617994...-science/t/how-moon-rocks-could-power-future/

Fusion Propulsion:
"Fusion is the only option that potentially achieves the most important regime for Solar-System travel: exhaust velocities of 105 to 106 m/s at thrust-to-weight ratios of 10-3. Such levels of performance allow both fast human transport and efficient cargo transport. There is no doubt that one of the most difficult problems that a peaceful world will face in the 21st century will be to secure an adequate, safe, clean, and economical source of energy. Existence of lunar helium-3, to be used as fuel for fusion reactors, is well documented; verified from numerous Apollo and Luna mission samples, current analyses indicate that there are at least 1 million tonnes embedded in the lunar surface. The helium-3 would be used as fuel for fusion reactors." Fusion Technology Institute of Wisconsin http://fti.neep.wisc.edu/research/dhe3

Robotic Mining Technology:
http://technology.infomine.com/robomine/
 
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  • #27
I should have been clearer, I meant fully mature technology or peer-reviewed research, not mission statements or opinion pieces. I'm well aware of the current state of projects like ITER but that is a far cry from even being proof of principle of what you have described.

Yes He3 is on the moon and yes there are large quantities but without fully realized technology we cannot meaningfully discuss the situation. We cannot examine the economical viability of mining without knowing exactly how much the efforts will cost, what the alternatives will be and what political and social factors will be in play. Looking at what we do know I am sceptical that anyone will make the effort to mine He3 for nuclear fusion fuel, the aforementioned first generation nuclear fusion reactors (based on ITER if it is a success) can be used to breed He3. I doubt we will ever get to the stage where sending vast robotic industries to the moon and other bodies is cheaper than simply having a number of dedicated 1stgen fusion reactors for breeding on Earth.
 
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  • #28
Maximilan said:
...but a power plant that can supply electricity might not come online for another 20 years after that...

:smile: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.
 
  • #29
JeffKoch said:
:smile: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

I disagree. We have made steady progress for the last 60+ years in confinement time and power using multiple confinement methods. Saying that it will never be a source of significant power generation seems to imply that we haven't made any progress. (to me at least) While it might not be a NEAR future approach, I have very little doubt that we will eventually reach power production.

Lucutus said:
What about Q2? Is it possible to calculate the energy if one of the two one gram objects were traveling at 1c, and the other 1 gram object were traveling at 0,999999c?

And, finally, my Q3 =)
Is it possible to calculate the energy of a collision if both 1 grams objects were traveling at 1c?

I ask these Q2 and Q3 because I have a vaguely memory that I read that calculations states that the energy would be infinitive when reaching 1c. Or is it only the energy needed to accelerate an object two 1c that becomes infinitive?

As has been said, getting to 1c is impossible. No matter how much energy you poured into an object, it would not approach c. However it's momentum would approach huge amounts near 1c.
 
  • #30
JeffKoch said:
:smile: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

WOW! Your grandpa knew about Helium 3 fusion prototypes being built before even Nuclear was on the block? Einstein must have been jealous. PLUS you got a time machine! Dang you da man - let me guess your ancestors were from Nibiru right?
 
  • #31
ryan_m_b said:
You've done the hard part, coming up with the idea, now just to solve the easy part, the engineering!

That's a little bit of sarcasm there because without overcoming the huge technical hurdles ideas like this are just interesting fantasies.

Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

JeffKoch said:
:smile: Our fathers and grandfathers said the same thing in the 1940's, but every time we get a little closer we find another very complex unanticipated collective phenomenon that makes it more difficult than we thought. I think our great great grandchildren would agree that fusion almost certainly will not play a significant role in the future of power generation, instead we will refine other, more elegant approaches.

Actually our fathers and grandfathers were all about fission. Fusion is a little newer than that. And I disagree I think fusion is probably going to be used unless we skip over it to something more efficient, but even then fusion energy will likely eventually be used as the cheap alternative for the poor people.

Maximilan said:
let me guess your ancestors were from Nibiru right?

:smile: Awesome reference that made me crack up!
 
  • #32
Monsterleg said:
Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

No offence but I am always surprised when people feel the need to say this. Ideas like this are always long term goals needing huge amounts of work in a variety of fields to even assess properly, which is fine as long as the limitations are realized and discussed. More often or not people simply propose 'fantastic answer X' and discuss the ramifications rather than the necessities of that idea.

Using your example yes; no one ever does wake up with a fully formed idea but once they have one they work out what all the known hurdles are, work out the hurdles of those hurdles and then set to work discussing the issue with as much information as possible. There is a big difference in discussing the feasibility of an idea and proposing it when there is no proper basis to be discussed.
 
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  • #33
Monsterleg said:
Hey don't forget that interesting fantasies are how we get the ideas for progress! If nobody ever had big dreams like that then we're not ever going to have that. No one woke up one day with some crazy new advanced concept they completely understood it and knew exactly how to prove it. That being said I'm going to go ahead and say mining the moon is probably a very very bad idea and that should most certainly not be our goal for mining extra terrestrial material.

I'm with Ryan on this one. It is exceedingly rare for something like this to happen, where someone just wakes up with an idea. The overwhelmingly vast majority of technolgical and scientific advances are a direct result of people working in a related field or on a specific problem. There are thousands if not millions of "concepts" of things that might be that people have every day. It is only when the applicable technologies are invented or improved that these things become feasible.
 
  • #34
Drakkith said:
I disagree. We have made steady progress for the last 60+ years in confinement time and power using multiple confinement methods. Saying that it will never be a source of significant power generation seems to imply that we haven't made any progress. (to me at least) While it might not be a NEAR future approach, I have very little doubt that we will eventually reach power production.

No, that certainly does not say that we have not made progress, it's patently obvious that we have made progress. The problem is that progress towards what we thought would be sufficient is never enough, the goal keeps moving farther back. So what seems like five yards forward winds up being one yard once we've run the five yards, moved the end zone back, and rescaled the field (analogy made explicit for the adolescents in the thread above). This has been going on for 60+ years, and this is just to reach a breakeven level at enormous expense - economical power production, competing with other established approaches including fission, is orders of magnitude harder than that. This is why I do not believe it will ever compete - there are many other lines of research, for example into efficient energy storage in batteries, that should have higher priority if providing electrical power to people is really the goal.
 
  • #35
JeffKoch said:
No, that certainly does not say that we have not made progress, it's patently obvious that we have made progress. The problem is that progress towards what we thought would be sufficient is never enough, the goal keeps moving farther back. So what seems like five yards forward winds up being one yard once we've run the five yards, moved the end zone back, and rescaled the field (analogy made explicit for the adolescents in the thread above). This has been going on for 60+ years, and this is just to reach a breakeven level at enormous expense - economical power production, competing with other established approaches including fission, is orders of magnitude harder than that. This is why I do not believe it will ever compete - there are many other lines of research, for example into efficient energy storage in batteries, that should have higher priority if providing electrical power to people is really the goal.

Well, this isn't the thread to debate fusion power, so all I'll say is that in my opinion we will get there and it will be competative.
 
  • #36
ryan_m_b said:
No offence but I am always surprised when people feel the need to say this. Ideas like this are always long term goals needing huge amounts of work in a variety of fields to even assess properly, which is fine as long as the limitations are realized and discussed. More often or not people simply propose 'fantastic answer X' and discuss the ramifications rather than the necessities of that idea.

Using your example yes; no one ever does wake up with a fully formed idea but once they have one they work out what all the known hurdles are, work out the hurdles of those hurdles and then set to work discussing the issue with as much information as possible. There is a big difference in discussing the feasibility of an idea and proposing it when there is no proper basis to be discussed.

So your saying that anytime anyone ever has an idea they should never tell anyone about it so they never set any long term goals in any field and the limitations are never realized and discussed. And if they don't have the correct qualifications or skill set and can't even overcome the first hurdle by them self then... I guess the idea might as well have never occurred. It's actually more likely that someone without a master's in physics will come up with a wonderful idea because they don't have all these entrenched concepts of what is and is not possible from years of memorizing and spitting out exactly what teachers want us to say, most of us convincing ourselves that all the popularly accepted theories are laws. Ideas, especially fantastical ones, are the foundation for any kind of progress. If you look at history you yourself can see patterns. Scientists ridiculed the idea of humans flying. Many people over the years tried to disprove them and failed. Yet the idea remained out there because someone proposed it without knowing exactly how to do it and someone finally made that idea a reality. If no one ever spoke of that idea because no one knew exactly how that would work then we would not have planes and everything resulting from that including the space program and the huge boon of technology off the 1960s space race. Actually let's just go back to being cavemen who don't know how to do anything. I'm not going to tell you about how if you rub your hands together it feels warm and we should try rubbing other things together to see what happens because frankly I don't know exactly how it works.

Basically your inherent idea of having to prove something before you even propose it being discussed is pretty much a paradox... Unless of course your some kind of science god and then you wouldn't need to propose it being discussed. I don't know if you realized but by responding to me you proposed the unfounded unestablished idea that in order for something to be discussed it must be established therefore your point is null and void merely by the fact that you posted that. AND even if you were right your response was discussing my unfounded and unestablished idea which apparently according to you shouldn't be discussed so by using our superior math skills you see your post does not equal what it would need to in order to be true therefore it is not a correct answer.

I want to make it clear I am in no way supporting the references to He3 mining, merely his idea of rather than establishing human colonies instead establishing robot outposts used as colonies or gas stations or trajectory adjusters etc. That is in no way a bad idea and sarcastically mocking him for posting it is just wrong. Next time you go to the future is there enough room in your time machine for me to come too? Little bit of sarcasm there because without overcoming the huge technical hurdles ideas like time machines are just interesting fantasies.

And Drakkith I don't think you really understood what I was attempting to say. But that's kind of wrong... The applicable technologies are invented or improved usually resulting from the idea that something should be invented or improved. Unless I'm misunderstanding you which I might.
 
  • #37
Monsterleg said:
So your saying that anytime anyone ever has an idea they should never tell anyone about it so they never set any long term goals in any field and the limitations are never realized and discussed.

Not at all, I was specifically saying the opposite of this.

Monsterleg said:
And if they don't have the correct qualifications or skill set and can't even overcome the first hurdle by them self then... I guess the idea might as well have never occurred.

Nope. What I was saying is that it's perfectly fine to have some ideas but it is pointless without acknowledging or raising the point of the technological hurdles.
Monsterleg said:
It's actually more likely that someone without a master's in physics will come up with a wonderful idea because they don't have all these entrenched concepts of what is and is not possible from years of memorizing and spitting out exactly what teachers want us to say, most of us convincing ourselves that all the popularly accepted theories are laws.

Ridiculous. Without the proper training your ideas will be inherently simple, not thought out and ultimately unworkable. The rest of your writing about master's degrees and education is drivel, proper education in science is not just spitting out answers.
Monsterleg said:
Ideas, especially fantastical ones, are the foundation for any kind of progress. If you look at history you yourself can see patterns. Scientists ridiculed the idea of humans flying. Many people over the years tried to disprove them and failed. Yet the idea remained out there because someone proposed it without knowing exactly how to do it and someone finally made that idea a reality. If no one ever spoke of that idea because no one knew exactly how that would work then we would not have planes and everything resulting from that including the space program and the huge boon of technology off the 1960s space race. Actually let's just go back to being cavemen who don't know how to do anything. I'm not going to tell you about how if you rub your hands together it feels warm and we should try rubbing other things together to see what happens because frankly I don't know exactly how it works.

For a start it is a fallacy that even if scientists ridiculed in the past and were wrong that it is wrong to always point out the flaws. Secondly the vast majority of knowledge and technology has been discovered and devised by scientists. You have a naive view that scientists occupy some clichéd ivory tower of dogma. You are also completely missing my point again. I have not said anything against coming up with ideas and proposing them, I was suggesting that discussion has to revolve around the exploration of the technological hurdles involved rather than a discussion of the ramifications of the technology.
Monsterleg said:
Basically your inherent idea of having to prove something before you even propose it being discussed is pretty much a paradox... Unless of course your some kind of science god and then you wouldn't need to propose it being discussed. I don't know if you realized but by responding to me you proposed the unfounded unestablished idea that in order for something to be discussed it must be established therefore your point is null and void merely by the fact that you posted that. AND even if you were right your response was discussing my unfounded and unestablished idea which apparently according to you shouldn't be discussed so by using our superior math skills you see your post does not equal what it would need to in order to be true therefore it is not a correct answer.

Rubbish, I have suggested nothing of the sort. Here is a very simple example for you;

I was opposing;
"Here is blue sky idea X. If we had blue sky idea we could do A, B, C, D, E..."

And encouraging;
"Here is blue sky idea X. I think that A, B, C, D, E...are all important technological hurdles to overcome. Here are my ideas about that, what are yours? I think it's important because with blue sky idea we could do A, B, C, D, E..."

So put simply I am encouraging discussion of the hurdles over discussion of the ramifications because without the former the latter cannot be done properly.
Monsterleg said:
I want to make it clear I am in no way supporting the references to He3 mining, merely his idea of rather than establishing human colonies instead establishing robot outposts used as colonies or gas stations or trajectory adjusters etc. That is in no way a bad idea and sarcastically mocking him for posting it is just wrong. Next time you go to the future is there enough room in your time machine for me to come too? Little bit of sarcasm there because without overcoming the huge technical hurdles ideas like time machines are just interesting fantasies.

Your tone here is completely out of order. I have not mocked anyone. You have completely misunderstood everything I have said and have then acted in an arrogant way towards a http://en.wikipedia.org/wiki/Straw_man" of what I have said.
 
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  • #38
So what your saying is you're not opposed to the proposition of a new idea, merely the way in which he was trying to use a farfetched idea to answer a problem without any foundation for it to actually be applicable?
If so that makes me feel a lot better. I get pretty irritated when people tell other people they aren't allowed to have ideas.

ryan_m_b said:
Ridiculous. Without the proper training your ideas will be inherently simple, not thought out and ultimately unworkable. The rest of your writing about master's degrees and education is drivel, proper education in science is not just spitting out answers.

That is a very simple concept I'm surprised your arguing this. Maybe you think I meant that someone without the skill set will make it a reality? No I meant that they can propose ideas that wouldn't normally be considered because they are removed from all the information. It's a pretty standard concept applying to every aspect of life not just science. Maybe I just didn't phrase it right. Someone who is disconnected from a situation often offers a new viewpoint or idea that hasn't already been assessed by those involved with it.
ryan_m_b said:
For a start it is a fallacy that even if scientists ridiculed in the past and were wrong that it is wrong to always point out the flaws. Secondly the vast majority of knowledge and technology has been discovered and devised by scientists. You have a naive view that scientists occupy some clichéd ivory tower of dogma.

Hahaha I feel like we're arguing about a relationship, how many times does one person drag up something from the past and the other person says that's not fair =p It is not wrong to point out the flaws because many scientists get carried away with assuming that the theories they are working under are fact. Yet historically many of the theories that are often purported as fact change completely over time. So the pattern shall continue today. Yes I believe that most scientists feel that they know everything which is partially why I'm working towards my degree, I plan on disproving as many scientific ideas as I can as well as proposing new ideas to work with. I do know a few scientists who are open-minded but the majority I have met and read about in articles are very arrogant and act like anyone without this education that I driveled all about is not even worth listening to. I don't know what your definition of scientist amounts to at this point because when talking about the vast amount of technology and knowledge we are talking about the entire history of the human race so I don't think I'll get into that it's too ambiguous. But I would like to note that different people place different value on different kinds of knowledge so that's probably better left out of your statement because knowledge is everything from how to pick your nose effectively and sneakily to what the color of a star 25 million light years away is. I would put my money on the nose-picking knowledge winning out as being more "useful" even though I personally would rather know about the star. Then it breaks down to did a scientist make that up and does more useful knowledge qualify as more knowledge and how can something like the color of a star be knowledge when we don't actually know it's just like 99% accurate and that would be an endless argument and a waste of time and no one would be right.

ryan_m_b said:
Your tone here is completely out of order. I have not mocked anyone. You have completely misunderstood everything I have said and have then acted in an arrogant way towards a strawman of what I have said.

I will apologize as it was my choice to behave that way regardless of what you did. I still feel like you mocked him but if it wasn't because of the idea itself just the way he was attempting to use it then I don't really care because I have no real interest in the whole He3 thing. I don't think I've ever seen strawman used like that that's pretty neat I'm going to keep mental note of that. Start throwing that at people and watch their confusion :smile:
 
  • #39
Monsterleg said:
That is a very simple concept I'm surprised your arguing this. Maybe you think I meant that someone without the skill set will make it a reality? No I meant that they can propose ideas that wouldn't normally be considered because they are removed from all the information. It's a pretty standard concept applying to every aspect of life not just science. Maybe I just didn't phrase it right. Someone who is disconnected from a situation often offers a new viewpoint or idea that hasn't already been assessed by those involved with it.

This is fine in every day situations where a new viewpoint can notice a problem or something. Your previous posts make it sound like NASA tourist B can barge into the control room, point out something on the screen, and suddenly everyone is like "Ohhh..." and bam, the satellite is fixed.

It is not wrong to point out the flaws because many scientists get carried away with assuming that the theories they are working under are fact.

This is a very widespread misconception. ALL of science is fact only to a certain accuracy. Newtons laws of motion ARE a fact. They work correctly in certain situations, and we use them in those situations. But they aren't 100% accurate and don't apply to everything. That doesn't make them wrong or not fact. Very few things turn out to be completely true or false or wrong or right.

Yet historically many of the theories that are often purported as fact change completely over time. So the pattern shall continue today.

Yes, just like relativity is proposed as fact currently, as is Quantum Mechanics. And they both ARE facts to the best degree that we can use that term. Again, they may not be 100% accurate and may change to give way to a more accurate theory, but that does not make them false.
Yes I believe that most scientists feel that they know everything which is partially why I'm working towards my degree, I plan on disproving as many scientific ideas as I can as well as proposing new ideas to work with.

Well, I hope you don't feel bad when you discover that there is a reason that only certain ideas are considered mainstream science.

I do know a few scientists who are open-minded but the majority I have met and read about in articles are very arrogant and act like anyone without this education that I driveled all about is not even worth listening to.

Have you ever considered that there might be a reason OTHER than them being arrogant and close minded that they don't listen to people?

I would put my money on the nose-picking knowledge winning out as being more "useful" even though I personally would rather know about the star.

That's nice but I don't see how the argument of what is "more useful" has any place here.

Then it breaks down to did a scientist make that up and does more useful knowledge qualify as more knowledge and how can something like the color of a star be knowledge when we don't actually know it's just like 99% accurate and that would be an endless argument and a waste of time and no one would be right.

If something is 99.99999999% accurate, you don't consider us to "know" it? If so, then no one knows anything, as nothing is 100% accurate.

Honestly you seem a little biased against "scientists". I'm not sure why. Do you not enjoy personal computers, air conditioning, mp3 players, comfy chairs, good food at a reasonable price, medicine, and millions of other things that never would have been developed had scientists not existed?
 
  • #40
And Drakkith I don't think you really understood what I was attempting to say. But that's kind of wrong... The applicable technologies are invented or improved usually resulting from the idea that something should be invented or improved. Unless I'm misunderstanding you which I might.

I'm saying that people don't wake up one day with crazy advanced concepts that then get worked out and made into reality. To me, crazy advanced concepts mean something that hands down isn't feasible at the time, at all. If yours is something less drastic, then maybe. It all depends on what you mean.

Edit: To me your post implies that this concept is thought of, and then a short time later with little difficulty it is made. Like the idea of a "backyard scientist" somehow proving all of science wrong and whatnot.
 
  • #41
Drakkith I'm kind of confused because I think you didn't understand most of what I said I'll do my best to clear it up.
Drakkith said:
This is fine in every day situations where a new viewpoint can notice a problem or something. Your previous posts make it sound like NASA tourist B can barge into the control room, point out something on the screen, and suddenly everyone is like "Ohhh..." and bam, the satellite is fixed.
Nonono that isn't what I meant at all lol. Although I will not refute that there is a possibility it could happen :-p

Drakkith said:
This is a very widespread misconception. ALL of science is fact only to a certain accuracy. Newtons laws of motion ARE a fact. They work correctly in certain situations, and we use them in those situations. But they aren't 100% accurate and don't apply to everything. That doesn't make them wrong or not fact. Very few things turn out to be completely true or false or wrong or right.
Using that argument I can say anything is fact... You're right nothing is 100% accurate so instead of saying everything is fact how about you say there are no facts, merely factors of varying accuracy. That helps your point a lot more than saying everything is fact just with different accuracies. It is more clear and is saying almost exactly the same thing. Except I guess your wording makes it sound like the statement goes against what I was saying and my wording supports it hmmmm. You should have brought up how every single theory is based upon other theories and that if we didn't assume that the foundation theories were fact then we'd never make any progress which beats my argument hands down. Then I'd say you have to draw a line because certain theories I'm willing to let be considered fact and certain theories I wouldn't. But then you can say well that would never work because drawing a line is a result of the opinion of whoever draws this line, plus you could then say that my whole argument about new ideas. New ideas are based not upon the solid foundation theories but generally are based off the theories I would consider too shaky. Then I would be beaten so my whole point about not treating theories as fact would be pointless. There you go. If I encourage the creation of new ideas in science, which I very much do, then I have to be able to consider current theories as fact.

Drakkith said:
Well, I hope you don't feel bad when you discover that there is a reason that only certain ideas are considered mainstream science.
I'm kind of confused by this statement but no I won't feel bad if I can't disprove anything because by the process of attempting to disprove it I give myself a very solid foundation to work with it if it survives. I'm not some conceited person who has to disprove everything I'm just a skeptical curious lad. I seek to learn as much as I can, hence my whole reason for arguing about such things, if you can give me an alternative way of thinking about something and "win" the argument I'm not going to be mad, I've just learned something new. I take it into account and reassess my own thoughts accordingly. That's why I enjoy discussions or arguments or whatever you want to call them because whatever happens I will learn something based on how you argue and if you happen to convince me of something I've learned a whole new way of thinking. It's a healthy process to always seek to learn.

Drakkith said:
Have you ever considered that there might be a reason OTHER than them being arrogant and close minded that they don't listen to people?
I have most definitely considered it I usually don't make rash generalizations about anything. It is a pattern I have repeatedly noticed even when they are currently wrong or they turn out to be wrong later.

Drakkith said:
That's nice but I don't see how the argument of what is "more useful" has any place here.
I was kinda making a little joke about all that it was completely irrelevant. Separate that paragraph into two sections and it'll make more sense to you.

Drakkith said:
If something is 99.99999999% accurate, you don't consider us to "know" it? If so, then no one knows anything, as nothing is 100% accurate.

Honestly you seem a little biased against "scientists". I'm not sure why. Do you not enjoy personal computers, air conditioning, mp3 players, comfy chairs, good food at a reasonable price, medicine, and millions of other things that never would have been developed had scientists not existed?
Once again that went along with the whole knowledge thing that was a little joke you obviously misunderstood.

You are very correct I am extremely biased against scientists. It's pretty ironic that I seek to be one. Idk... I kind of wish I lived in the medieval ages I would be an awesome knight. But yes I guess even knights need science.

Drakkith said:
I'm saying that people don't wake up one day with crazy advanced concepts that then get worked out and made into reality. To me, crazy advanced concepts mean something that hands down isn't feasible at the time, at all. If yours is something less drastic, then maybe. It all depends on what you mean.

Edit: To me your post implies that this concept is thought of, and then a short time later with little difficulty it is made. Like the idea of a "backyard scientist" somehow proving all of science wrong and whatnot.
That is not what I was saying at all. In "fact" :-p you just reiterated a point I had been attempting to make earlier.
 
  • #42
Monster, I have no idea what you are getting at. You don't make any sense and seem to contradict half of what you said previously, and I for one do NOT like to argue. It just irritates me. Also, this is a forum, so unless you REALLY make it clear that you're joking with something, then it most likely isn't going to be taken as a joke at all.
 
  • #43
I too have no idea where this thread has gone. You do seem to have a severe misunderstanding of what science is Monster and what scientists actually do. You say you want to disprove as many scientific theories as possible? This is what science is all about! We all spend every hour working as hard as possible to test established knowledge to destruction. But when something works a billion times in a row in the same conditions you don't expect it to change the billionth and first (and if it did you would suspect some hidden factor has changed and would be prompted to look for that). Good luck in your degree, if it is in science I'm sure you will be happy to see how it really works.
 
  • #45
Maximilan said:

The problem with antimatter, apart from the fact we cannot contain it nor make it in usable quantities, is that if we could manufacture and store it we have just created the worst weapon ever. How would you feel knowing that flying around the system were ships that could decimate most of the life on Earth just by crashing into it?

In my opinion it often gets overlooked that if we did attain the horrendous energies needed for space travel there are very bad implications. It's akin to fitting every commercial jet with a nuclear bomb ready to go off at the slightest nudge.
 
  • #46
Ryan_m_b said:
In my opinion it often gets overlooked that if we did attain the horrendous energies needed for space travel there are very bad implications. It's akin to fitting every commercial jet with a nuclear bomb ready to go off at the slightest nudge.

But which is more likely: will man listen to the voice of caution, or continue to strain even more to hear the faint whispers that come back from the dark at CERN? (dun - dun - dun)

"In what distant deeps or skies
Burnt the fire of thine eyes?
On what wings dare he aspire?
What the hand dare seize the fire?"
- William Blake



My apologies to the original poster for side tracking this thread - this will be my last post. Thank you guys for your input, I think I'm good to go for my shot at Sci-Fi :)
 
  • #47
Ryan_m_b said:
It wouldn't matter if it increased its acceleration, it just needs to have a constant acceleration but there are problems with this:

A) Supplying it with enough fuel to get to 0.99c - taking a http://en.wikipedia.org/wiki/VASIMR" as the best speculative ion drive with a specific impulse of 30,000 seconds you would need ~1000 parts kg fuel for every 1kg of ship

B) Having enough thrust to reach 0.99c in a reasonable time - taking VASIMR again if we assume a 1 tonne ship with 1000 tonnes of fuel then with a thrust of http://en.wikipedia.org/wiki/Ion_thruster#Comparisons" the ship will be capable of an average acceleration of 1e-6 and would reach 0.99c in roughly a million years.

C) All the other engineering issues of energy, waste heat etc
What do you mean move through a shorter space? From all reference frames the ship would have traveled the same distance.

I was talking about from an observational point of view but yes I agree, it will have still covered the same distance although it might appear time and length contraction concerns would seem somewhat different dependant on the non relativistic observer, naively at least.
 
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  • #48
Maximilan said:
But which is more likely: will man listen to the voice of caution, or continue to strain even more to hear the faint whispers that come back from the dark at CERN? (dun - dun - dun)

"In what distant deeps or skies
Burnt the fire of thine eyes?
On what wings dare he aspire?
What the hand dare seize the fire?"
- William Blake

My apologies to the original poster for side tracking this thread - this will be my last post. Thank you guys for your input, I think I'm good to go for my shot at Sci-Fi :)

Well the Pandora's box of nuclear warfare has been open for over 60 years now and despite coming close we had the sense not to have a war of that kind. The argument of "it's there therefore it will be done" does not stick I'm afraid. The idea of some countries getting nuclear weapons is enough to invoke a worldwide diplomatic crisis, imagine how it would be if you proposed building vehicles that could wipe out the planet?
 

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