Flying is impossible, so is timetravel.

[QuantumTheory]

People in the 1800's though flying was impossible. How can you take metal weighing several tons and fly with it? But look where we are now in only 100 years.

Well, so now people are saying time travel is impossible. It may be, but it just *may* be possible in the future. Maybe we do not know enough about quantum physics yet.

I am fasinated by time travel, it may be fantasy, but it may just be possible. I'm aware of the grandfather paradox and other ones, as some say this is proof that you can't, but there may be other loopholes, so tos peak.

 

[chroot]

Achieving flight was only a matter of advancing technology; we observed that other things fly (birds, bees, etc.) long before we attempted it ourselves.

On the other hand, time travel appears to be prohibited by physical laws, and nothing has ever been observed to travel through time. If our understanding of those laws is correct, no amount of technological progress will allow us to break them.

- Warren

 

[arildno]

Scientists in the 1800's were skeptical as to whether flight as we have it today (a plane flying without a bird-like flapping mechanism) was possible, because you cannot generate circulation (and in conjunction with that, fligfht) in an inviscid fluid (although an inviscid fluid may maintain a given circulation). Thus, it all depended on whether the viscosity of air could be sufficient or not to generate the necessary circulation.
Some scientists thought it might be sufficient, others doubted that.

As for time travel, I believe the disbelievers have a more solid basis for their skepticism than this type of quantitative guesswork.

 

[QuantumTheory]

viscosity if air?

 

[Curious3141]

Achieving flight was only a matter of advancing technology; we observed that other things fly (birds, bees, etc.) long before we attempted it ourselves.

On the other hand, time travel appears to be prohibited by physical laws, and nothing has ever been observed to travel through time. If our understanding of those laws is correct, no amount of technological progress will allow us to break them.

- Warren

That's actually a pretty big "if". I remember reading a reply from Isaac Asimov to one of his correspondents in a science fiction magazine. The correspondent had said that no one should be dogmatic about something physically "impossible" like superluminal travel, that men once thought the steam engine and flight were impossible.

Asimov had replied (rather patronisingly I thought) that steam engine and flight were feats of engineering, whereas superluminal travel was forbidden by physical law.

At the time, I agreed with this sort of dogmatic attitude; now I'm not so sure. Newton's formulation of physical law was considered completely sound till Einstein came along and demolished it at its foundations. We currently believe our understanding to be sound, but there's absolutely no guarantee a genius isn't going to come along tomorrow and make fools out of us all.

 

[Pengwuino]

But isn't it also true that we are far more capable of testing things where Newton and pre-20th century physicists couldn't. Newton couldn't test near the speed of light but we are able to do it and we do notice this whole, E->inf problem and divide by 0 stuff and unless mathematics starts taking a strange turn for hte worse, it's probably not going to happen.

I bet if any of this stuff DOES happen, it's going to be some really strange concept with stuff we don't even experience or know of. With things like flight, we had hints that it was possible and the idea was not all that far-fetched. The problem here is we don't see birds traveling through time and I've heard we have measured causality to some very precise standards...

 

[ZapperZ]

That's actually a pretty big "if". I remember reading a reply from Isaac Asimov to one of his correspondents in a science fiction magazine. The correspondent had said that no one should be dogmatic about something physically "impossible" like superluminal travel, that men once thought the steam engine and flight were impossible.
Asimov had replied (rather patronisingly I thought) that steam engine and flight were feats of engineering, whereas superluminal travel was forbidden by physical law.
At the time, I agreed with this sort of dogmatic attitude; now I'm not so sure. Newton's formulation of physical law was considered completely sound till Einstein came along and demolished it at its foundations. We currently believe our understanding to be sound, but there's absolutely no guarantee a genius isn't going to come along tomorrow and make fools out of us all.

Then on what basis does one answer a question like this? If you are suggesting that everything MIGHT be possible, then what's the purpose of asking these types of questions in the first place? If the OP wants an answer based on our current understanding of the physical universe, then that's the kind of responses one will get. If the OP wants to be based on "what might be possible via speculation not based on current understanding", then why bother asking because the question has an automatic answer!

If we want to play the speculation game, then all bets are off. I can make things up as well as the next quack. What keeps us grounded IS the established physics. Ironically, it is also what keeps us physicists motivated to explore beyond its boundaries.

Zz.

 

[russ_watters]

That's actually a pretty big "if".

How so? Relativity is pretty thoroughly tested.

The "anything is possible" and "people used to think flying was impossible" arguments are common misunderstandings of science, mostly based on factual errors in knowledge, such as...

At the time, I agreed with this sort of dogmatic attitude; now I'm not so sure. Newton's formulation of physical law was considered completely sound till Einstein came along and demolished it at its foundations.

No, they weren't. Newton's laws were known to be flawed not long after (immediately after?) they were formulated. Why do you think Einstein (among others) was looking for a new theory? [edit: actually, does anyone know who was first to realize the Mercury issue?]

In addition, Einstein's theory does not change the accuracy of Newton's theory. If Newton's theory was 1% off in calculating an orbit 200 years ago, it is still 1% off in calculating that orbit today. And the same applies to Relativity: scientists have been able to accelerate objects up to a very high fraction of the speed of light, verifying the theory to an extrordinarily level of precision. Finding a new theory will not retroactively change that experimental data.

[edit] Also, people think about Newton's gravity, but don't think about what Newton's laws of kinematics have to say about the speed of light. Newton's gravity may have been accurate to within a couple of percent, but scientists were nowhere close to measuring the speed of light at the time, much less accelerating an object to any significant fraction of it.

[edit2] The best I can find about timing of the discoveries of flaws in Newton's theory was Laplace in the early 1800s. Anyone know of anyone earlier? That gets us 150 years, but with the rate of advancement of our ability to test Newton's theories at the time, that's pretty quick.

 

[Astronuc]

One should also consider the energy and more particularly the energy density required to bring matter to the near speed of light.

But then one can argue - one might be able to 'warp' space, which usually requires a large mass or some huge energy.

Now compare that to the conditions under which humans 'live'.

 

[QuantumTheory]

One should also consider the energy and more particularly the energy density required to bring matter to the near speed of light.
But then one can argue - one might be able to 'warp' space, which usually requires a large mass or some huge energy.
Now compare that to the conditions under which humans 'live'.

Some people were obviously inspired by seeing birds fly, to make airplanes, but honestly, many people did *not* think it was possible. People also thought the Earth was flat. And this was a misunderstanding. Everything can be a misunderstanding.

Also, physicsts have been able to make music submatoimfc particles travel at the speed of light, about 2x as fast. I saw this on the science channel on time travel. They used a laser and encoded music on it, I believe. However, I do realize atoms behave differently than humans, it is cool though.

 

[QuantumTheory]

How so? Relativity is pretty thoroughly tested.
The "anything is possible" and "people used to think flying was impossible" arguments are common misunderstandings of science, mostly based on factual errors in knowledge, such as... No, they weren't. Newton's laws were known to be flawed not long after (immediately after?) they were formulated. Why do you think Einstein (among others) was looking for a new theory? [edit: actually, does anyone know who was first to realize the Mercury issue?]
In addition, Einstein's theory does not change the accuracy of Newton's theory. If Newton's theory was 1% off in calculating an orbit 200 years ago, it is still 1% off in calculating that orbit today. And the same applies to Relativity: scientists have been able to accelerate objects up to a very high fraction of the speed of light, verifying the theory to an extrordinarily level of precision. Finding a new theory will not retroactively change that experimental data.
[edit] Also, people think about Newton's gravity, but don't think about what Newton's laws of kinematics have to say about the speed of light. Newton's gravity may have been accurate to within a couple of percent, but scientists were nowhere close to measuring the speed of light at the time, much less accelerating an object to any significant fraction of it.
[edit2] The best I can find about timing of the discoveries of flaws in Newton's theory was Laplace in the early 1800s. Anyone know of anyone earlier? That gets us 150 years, but with the rate of advancement of our ability to test Newton's theories at the time, that's pretty quick.

'

Sorry, as I am only 17 and am not that experineced in physics. But aren't there supposed to be other' theories' to getting to do time traevl *theortically* besides relativeiy? I also heard that general relativiy (or is it special?) DOES allow it.

 

[Artman]

The ancient Egyptians in 200 bc played with model birds that looked like airplanes (replicas have been made of the artifacts and tested. They flew.)

http://www.catchpenny.org/model.html"

Flying machines were designed by DaVinci in the 1480s (though never built.), in the late 1783 man had achieved lighter than air flight in a balloon and the first manned glider was built in the mid 1800s and flown by a child.

So in 1800 the idea was pretty well developed that man could someday fly.

 

[Danger]

Some people were obviously inspired by seeing birds fly, to make airplanes, but honestly, many people did *not* think it was possible.

As with such things as evolution today, it was primarily non-scientists who disbelieved. Those in the business of finding things out knew that something was wrong when all of the calculations indicated that a bumblebee can't fly. (They had failed to factor in the wingtip vortices that increase lift.)

Also, physicsts have been able to make music submatoimfc particles travel at the speed of light, about 2x as fast. I saw this on the science channel on time travel.

Although I never saw the show, this is either a bad program or a misunderstanding on your part of what was achieved. To start with, music is not made of particles. It's simply information encoded in some manner (in this case, as modulated photons). There's no way that it went faster than light, because photons are light.

 

[zoobyshoe]

Time Travel By Internal Holodeck

Most people have probably heard of a "fashback". This is associated in people's minds with LSD users and Vietnam Veterans, but some people who have temporal lobe seizures also have them. A "flashback" is a sudden hallucination that the person is surrounded by a past environment. This can be mild,in the form of seeming to see unmoving photographs of the past superimposed on their field of vision, to full blown: three dimensional, past environments surrounding them on all sides with accompanying sounds, smells, and tactile qualities. It seems that when sense memories are juiced up by the surge of neuronal activity that constitutes seizure activity the result can be as if we all had a kind of built in holodeck.

There is a Canadian researcher, Robert Persinger, who has been experimenting for many years with the effects of magnetic fields on the brain, and there's a strong indication that this could be configured to cause a "holodeck-like" experience: full blow hallucinations of being in a different environment. To the extent a person constructs that hallucination with elements of their own memory then something indistinguishable from deliberate travel to the past and back is concievable.

There's likewise no reason a person couldn't hallucinate being in a future environment. For some, that would probably be a whacky and unrealistic fantasy or science fiction future, but for the more level headed it would be a conservative, plausible picture. In any event, since these pictures are created from the person's own store of sensory data, and in accordance with their ways of thinking, the result would always be particularly persuasive to them. They would feel dead on accurate.

So, if a Doc Brown shows up with a DeLorean that seems to be able to take you to the past or future, it's a very, very good bet that it would be creating a controlled, deliberate kind of flashback (or "flashforward") by utilizing your own pre-existing capacity to create a "holodeck-like" experience. If that Doc Brown has a penchant for "fooling himself" as Feynman might put it, or if he is a con-man, you might also hear claims that his time machine proves that the laws of physics aren't what we thought.

 

[ComputerGeek]

People in the 1800's though flying was impossible. How can you take metal weighing several tons and fly with it? But look where we are now in only 100 years.
Well, so now people are saying time travel is impossible. It may be, but it just *may* be possible in the future. Maybe we do not know enough about quantum physics yet.
I am fasinated by time travel, it may be fantasy, but it may just be possible. I'm aware of the grandfather paradox and other ones, as some say this is proof that you can't, but there may be other loopholes, so tos peak.

your off a little bit.

Pre-flight times, people had an intuitive belief that flight was impossible for a machine...

For time travel, we have mathematics to describe why it would be very difficult and impracticle (but possible as outlined by kip thorn in a few of his books)

 

[Moonbear]

The difference between flying and time travel is that with flying, people did know that flight was possible by watching birds and insects. What they didn't think was possible was designing/building a device that would allow much heavier humans to fly. The concept of flight was not considered impossible, the idea of humans (or anything else heavier than a bird) flying is what drew the attention of skeptics.

With time travel, it's not that we observe things traveling through time and just don't know how to make people do it; there's simply no evidence that anything can travel through time, and no indication that anything lingers in some sort of past time. Afterall, are you splitting off and forming a whole new body every fraction of a second that something changes so that your previous state is preserved in the past?

 

[ComputerGeek]

Most people have probably heard of a "fashback". This is associated in people's minds with LSD users and Vietnam Veterans, but some people who have temporal lobe seizures also have them. A "flashback" is a sudden hallucination that the person is surrounded by a past environment. This can be mild,in the form of seeming to see unmoving photographs of the past superimposed on their field of vision, to full blown: three dimensional, past environments surrounding them on all sides with accompanying sounds, smells, and tactile qualities. It seems that when sense memories are juiced up by the surge of neuronal activity that constitutes seizure activity the result can be as if we all had a kind of built in holodeck...

What would be weird is if that person could affect the past :-)

 

[zoobyshoe]

What would be weird is if that person could affect the past :-)

Depending on the vividness of the experience, they ought to be able to interact with everything there as if it were completely real. When they get "back to the future", though, nothing they did would have changed the authentic present, just like nothing that happens on the holodeck of the enterprise carries over into real life. If it ever does, then you know you're still in the holodeck.

 

[waht]

One cannot prove absoluteness of our laws of physics, therefore the concept of time travel is neither right nor wrong.

The only way to make big progress or a quantum leap in science is to ponder on such concepts and not disregard them because some physicist tells you otherwise.

 

[russ_watters]

Some people were obviously inspired by seeing birds fly, to make airplanes, but honestly, many people did *not* think it was possible. People also thought the Earth was flat.

And in both cases, such people were not scientists. That the Earth was believed to be flat by scientists (or their predicessors) is another similar myth. Every halfway educated person who lived in about the last 2000 years knew the Earth was round. Most notably, an Egyptian (?) named Eratosthenes in 250BC came up with a viable way to measure the circumference of the Earth (unfortunately, we don't know how well he did, since no one knows how long the unit of distance he used is). He also measured the distance to the moon and the tilt of the Earth's axis wrt to the ecliptic (yeah, that's right: he knew the sky wasn't just some spherical shell). Google him...

Sorry, as I am only 17 and am not that experineced in physics. But aren't there supposed to be other' theories' to getting to do time traevl *theortically* besides relativeiy? I also heard that general relativiy (or is it special?) DOES allow it.

You need to be a little more specific about what you mean by time travel because, quite obviously, we are all traveling through time right now. But if you are looking for a way to go back and meet your parents before you were born... no.

I know it's a real kick in the teeth when you first learn about how our current knowledge of science puts limits on our future discoveries, but that really is a reality.

 

[ZapperZ]

One cannot prove absoluteness of our laws of physics, therefore the concept of time travel is neither right nor wrong.

No one has said anything about "prove". I have, however, talked about VALIDITY. If you don't think many parts of physics today is valid, then you should stop using your electronics because you are using faulty ideas.

The only way to make big progress or a quantum leap in science is to ponder on such concepts and not disregard them because some physicist tells you otherwise.

So someone who is ignorant of basic physics has more of an authority on such a matter than a physicist? This is the source of quackery. Imagination without knowledge is ignorance waiting to happen. It is why so many people are often duped into these mumbo-jumbo scheme, and then they whine that they got taken in by these con artists.

I'm not saying physicists are always right. The nature of our profession is such that we are EMPLOYED to go beyond what we know and what has been already established. However, that statement of your is irresponsible in the sense that it belittles the accomplishments that have been achieved. It is these accomplishments that we offer as PROOF that we're not just blowing smoke into the air with no substance. You are providing proof of this yourself every single day even if you're ignorant of it.

Zz.

 

[quantumdude]

Well, so now people are saying time travel is impossible.

What? Who says that? Why, right now I'm moving through time at a rate of 60 seconds per minute!

 

[chroot]

What? Who says that? Why, right now I'm moving through time at a rate of 60 seconds per minute!

Unitless speed! Egads!

- Warren

 

[rachmaninoff]

Unitless speed! Egads!
- Warren

You're misusing nomenclature! "Speed" does not have units of seconds/second. We need a new word for this. I recommend we call it velocirapidity, and we let the SI unit, the velociraptor, be equal to one fortnight per nanosecond.

 

[Curious3141]

Then on what basis does one answer a question like this? If you are suggesting that everything MIGHT be possible, then what's the purpose of asking these types of questions in the first place? If the OP wants an answer based on our current understanding of the physical universe, then that's the kind of responses one will get. If the OP wants to be based on "what might be possible via speculation not based on current understanding", then why bother asking because the question has an automatic answer!
If we want to play the speculation game, then all bets are off. I can make things up as well as the next quack. What keeps us grounded IS the established physics. Ironically, it is also what keeps us physicists motivated to explore beyond its boundaries.
Zz.

I am saying that no one should be immediately dismissive. To me, the proper way to answer such a question is : based on our current understanding, we can see no way of doing it.

For the record, I was actually endorsing the way chroot answered the question. Not many others would have prefaced the answer with that (warranted) circumspection.

 

[chroot]

You're misusing nomenclature! "Speed" does not have units of seconds/second. We need a new word for this. I recommend we call it velocirapidity, and we let the SI unit, the velociraptor, be equal to one fortnight per nanosecond.

Now that is standing on the shoulders of giants!

- Warren

 

[Curious3141]

How so? Relativity is pretty thoroughly tested.

Actually, I thought Newton's theories were tested pretty thoroughly before Newton's formulation and after them.

The "anything is possible" and "people used to think flying was impossible" arguments are common misunderstandings of science, mostly based on factual errors in knowledge, such as... No, they weren't. Newton's laws were known to be flawed not long after (immediately after?) they were formulated. Why do you think Einstein (among others) was looking for a new theory? [edit: actually, does anyone know who was first to realize the Mercury issue?]

This is stretching the truth. The anomalous advance of Mercury's perihelion was first observed by Leverrier around 1840 I think. Newton published his theory of universal gravitation around 1665. That's 175 years ! Now how long has the theory of relativity been around ?

In addition, Einstein's theory does not change the accuracy of Newton's theory. If Newton's theory was 1% off in calculating an orbit 200 years ago, it is still 1% off in calculating that orbit today. And the same applies to Relativity: scientists have been able to accelerate objects up to a very high fraction of the speed of light, verifying the theory to an extrordinarily level of precision. Finding a new theory will not retroactively change that experimental data.

Yes, but that defect in accuracy meant that the theory itself was fundamentally flawed ! What is troubling is that the accepted standards for good accuracy or precision do change (a lot) with advancing technology. In Newton's time, I'm sure 1 % would've been regarded as minute - in fact, many before Einstein *did* dismiss that slight anomaly in Mercury's orbit to be unavoidable experimental error. Such an error would raise alarm bells today when applied to any experiment, but perhaps an error like 10^(-3)% would not. However, it may be in precisely that tiny an anomaly that may demolish an established theory and bring in a new one. Without being able to confidently measure at that level of precision and accuracy, we won't know (for now).

[edit] Also, people think about Newton's gravity, but don't think about what Newton's laws of kinematics have to say about the speed of light. Newton's gravity may have been accurate to within a couple of percent, but scientists were nowhere close to measuring the speed of light at the time, much less accelerating an object to any significant fraction of it.

Actually, I was thinking of SR even more than GR when I made my post. So many basic things changed from Newton -> Einstein. The Newtonian formula for kinetic energy E = 1/2*m*v^2 was simply a first order approximation of E = mc^2 in SR. Without the tools to measure the requisite anomalies, the error would never have been realized.
All I'm saying is keep an open mind - the theories exalted as sacrosanct today may well prove utterly wrong tomorrow. That's no reason to disregard them - just...accept their validity as being permanently provisional.

[edit2] The best I can find about timing of the discoveries of flaws in Newton's theory was Laplace in the early 1800s. Anyone know of anyone earlier? That gets us 150 years, but with the rate of advancement of our ability to test Newton's theories at the time, that's pretty quick.

I thought it was Leverrier in 1840. The dates are close enough, though.

 

[Ivan Seeking]

And in both cases, such people were not scientists.

According to Igor Novikov, p 57 of The Future of Spacetime, 2002:

First, in 1895, another outstanding physicist, Lord Kelvin, then president of the Royal Society, claimed that "heavier-than-air flying machines are impossible". Lord Kelvin's claim was based on the best understanding of physics at that time. However, as we know, the first flight by the Wright brothers was achieved in 1903, only a few years later.

 

[Pengwuino]

I think one thing to note here is that if time travel were possible and currently happening... we wouldn't have a clue that it is since these things or peopel woudl be in and out of our 'time frame' in an instant. A lot of strange problems would be occurring as well, philisophical and scientific. When we say things in quantum mechanics are probabilities... I would assume there has to be some huge problems since the idea of natural randomness could no longer exist if everything already has been pre-determined.

 

[Curious3141]

According to Igor Novikov, p 57 of The Future of Spacetime, 2002:

Bit curious about the basis for that statement (made by Kelvin). He did know that birds et al are "heavier than air flying machines" right ?

 

[zoobyshoe]

Bit curious about the basis for that statement (made by Kelvin). He did know that birds et al are "heavier than air flying machines" right ?

Apparently he was famous for overconfident pronouncements:

Scottish mathematician and physicist who contributed to many branches of physics. He was known for his self-confidence, and as an undergraduate at Cambridge he thought himself the sure "Senior Wrangler" (the name given to the student who scored highest on the Cambridge mathematical Tripos exam). After taking the exam he asked his servant, "Oh, just run down to the Senate House, will you, and see who is Second Wrangler." The servant returned and informed him, "You, sir!" (Campbell and Higgens, p. 98, 1984). Another example of his hubris is provided by his 1895 statement "heavier-than-air flying machines are impossible" (Australian Institute of Physics), followed by his 1896 statement, "I have not the smallest molecule of faith in aerial navigation other than ballooning...I would not care to be a member of the Aeronautical Society." Kelvin is also known for an address to an assemblage of physicists at the British Association for the advancement of Science in 1900 in which he stated, "There is nothing new to be discovered in physics now. All that remains is more and more precise measurement."

http://scienceworld.wolfram.com/biography/Kelvin.html

Also:

Here are some famous skeptical quotes by William Thomson

"Heavier-than-air flying machines are impossible"

"Radio has no future"

"X-rays are a hoax"

http://members.tripod.com/~Irishscientists/scientists/KELV.HTM

 

[russ_watters]

Actually, I thought Newton's theories were tested pretty thoroughly before Newton's formulation and after them.

They weren't. While Newton's gravity was tested to perhaps a couple of percent and over short periods of time (good, but not great), Newton's theories on kinematics weren't even tested to with a thousandth of a percent of the speed of light.

This is stretching the truth. The anomalous advance of Mercury's perihelion was first observed by Leverrier around 1840 I think. Newton published his theory of universal gravitation around 1665. That's 175 years ! Now how long has the theory of relativity been around ?

Timewise, it was longer than I realized [actually, I misread something that implied Laplace found some anomalies 50 years earlier], but how much happened in science between those two events? How much better did our measurement capabilities get compared with, say, the past 100 years? At the turn of the century, we couldn't accelerate objects to even 1/1000th the speed of light - within decades, they were sending electrons up to 99.9999...% of the speed of light.

Yes, but that defect in accuracy meant that the theory itself was fundamentally flawed ! What is troubling is that the accepted standards for good accuracy or precision do change (a lot) with advancing technology.

I don't find that troubling - Newton's theories were good enough to cover everything known at the time. Theories don't get much more solid than that!

It's only natural that if you can only test to within 1%, you make judgements based on that. If you can get to 99.99999999% the speed of light, then you make your judgements based on that.

However, it may be in precisely that tiny an anomaly that may demolish an established theory and bring in a new one.

I wouldn't use the word "demolish" - Newton's theories may be fundamentally flawed, but they are still used because they are still useful.

Similarly, any theory that replaces Relativity will necessarily incorporate all that is known about relativity to date. And if it's simpler, people will still use relativity in appropriate situations.

Ill I'm saying is keep an open mind - the theories exalted as sacrosanct today may well prove utterly wrong tomorrow.

Again, you think I'm being too absolute in my acceptance, I think you are being too absolute in your rejection. Not even Newton's theories are considered "utterly wrong".

 

[russ_watters]

According to Igor Novikov, p 57 of The Future of Spacetime, 2002: [re: Kelvin]

As noted, that's a pretty rediculous statement considering I'm sure he'd seen birds before. But perhaps he was talking about technology, not science...?

 

[Curious3141]

They weren't. While Newton's gravity was tested to perhaps a couple of percent and over short periods of time (good, but not great), Newton's theories on kinematics weren't even tested to with a thousandth of a percent of the speed of light. Timewise, it was longer than I realized [actually, I misread something that implied Laplace found some anomalies 50 years earlier], but how much happened in science between those two events? How much better did our measurement capabilities get compared with, say, the past 100 years? At the turn of the century, we couldn't accelerate objects to even 1/1000th the speed of light - within decades, they were sending electrons up to 99.9999...% of the speed of light. I don't find that troubling - Newton's theories were good enough to cover everything known at the time. Theories don't get much more solid than that!
It's only natural that if you can only test to within 1%, you make judgements based on that. If you can get to 99.99999999% the speed of light, then you make your judgements based on that. I wouldn't use the word "demolish" - Newton's theories may be fundamentally flawed, but they are still used because they are still useful.
Similarly, any theory that replaces Relativity will necessarily incorporate all that is known about relativity to date. And if it's simpler, people will still use relativity in appropriate situations. Again, you think I'm being too absolute in my acceptance, I think you are being too absolute in your rejection. Not even Newton's theories are considered "utterly wrong".

I agree with most of your points. I'm not being too "absolute" in my rejection of anything (even Newton), merely pointing out that violent changes in paradigms and dogma can result almost overnight with even miniscule observations. This is well borne-out in the history of science. The (relativistic) idea that motion could alter the fabric of space time would've been considered utterly revolutionary in Newton's time, for instance. In fact, if someone as brilliant as Einstein had proposed the idea back then (without the necessary experimental evidence, for it wouldn't have been forthcoming), he would have been laughed at as a fool. Knowing something of how unpleasant Newton was as a person, he would probably have branded this guy a heretic and had his chuch friends do some horrid Braveheart type stuff to him.

 

[QuantumTheory]

I think one thing to note here is that if time travel were possible and currently happening... we wouldn't have a clue that it is since these things or peopel woudl be in and out of our 'time frame' in an instant. A lot of strange problems would be occurring as well, philisophical and scientific. When we say things in quantum mechanics are probabilities... I would assume there has to be some huge problems since the idea of natural randomness could no longer exist if everything already has been pre-determined.

Thank you! This is what I was trying to say!

What I mean't was, this program was credible! It also had one of the few pioneers int ime travel, Kip. Also, it was on the science channel (By discovery) Everything on there is fact. There was also one on quantum physics abuot what is light, a wave or a particle? It is both. I learned so much. It is great

What i meant was, as someone else mentioned, we caused subatomic particles to go 99.999999999% the speed of light. This is what I meant. they encoded these on a music lase beam, and sent them across the room. It didn't go anywhere, but it was cool and they were able to get the speed. In fact, they said it went 2x the speed of light. You may not believe it, i just wish i wouldve written down the names..

 

[TheStatutoryApe]

Although I never saw the show, this is either a bad program or a misunderstanding on your part of what was achieved. To start with, music is not made of particles. It's simply information encoded in some manner (in this case, as modulated photons). There's no way that it went faster than light, because photons are light.

If this is the show I am thinking of I don't think it was a very good one.
I was quite suprised when a friend of mine told me that the way Superman taveled back in time by flying around the Earth really fast wasn't so silly a notion. I think it made him feel bad when I started laughing. He then showed me a program on television on discovery channel or something that actually said this.

 

[Pengwuino]

What i meant was, as someone else mentioned, we caused subatomic particles to go 99.999999999% the speed of light. This is what I meant. they encoded these on a music lase beam, and sent them across the room. It didn't go anywhere, but it was cool and they were able to get the speed. In fact, they said it went 2x the speed of light. You may not believe it, i just wish i wouldve written down the names..

They didn't, trust me. Someone else will be able to explain what they ACTUALLY did.

 

[TheStatutoryApe]

Thank you! This is what I was trying to say!
What I mean't was, this program was credible! It also had one of the few pioneers int ime travel, Kip. Also, it was on the science channel (By discovery) Everything on there is fact. There was also one on quantum physics abuot what is light, a wave or a particle? It is both. I learned so much. It is great
What i meant was, as someone else mentioned, we caused subatomic particles to go 99.999999999% the speed of light. This is what I meant. they encoded these on a music lase beam, and sent them across the room. It didn't go anywhere, but it was cool and they were able to get the speed. In fact, they said it went 2x the speed of light. You may not believe it, i just wish i wouldve written down the names..

Ok maybe I'm not thinking of the same show but I still had to share that story.

 

[QuantumTheory]

If this is the show I am thinking of I don't think it was a very good one.
I was quite suprised when a friend of mine told me that the way Superman taveled back in time by flying around the Earth really fast wasn't so silly a notion. I think it made him feel bad when I started laughing. He then showed me a program on television on discovery channel or something that actually said this.

Actually, on Discovery channel and the science channel, they have several about time travel and quantum physics. It was merely to illustrate a point. The point was, as I recall, that if you COULD go faster thant he speed of light you would theortically go backwards in time. Of course, nothing can go faster than Light (C) but it was just an EXAMPLE.

The show was actually quite accurate. Do you really think the science channel would show a show that is not 'very good'? Of course, it is controverisal, no one really knows for sure -- because no one can prove it. But they mentioned it was highly inprobably as well.

 

[Pengwuino]

Actually, on Discovery channel and the science channel, they have several about time travel and quantum physics. It was merely to illustrate a point. The point was, as I recall, that if you COULD go faster thant he speed of light you would theortically go backwards in time. Of course, nothing can go faster than Light (C) but it was just an EXAMPLE.

The show was actually quite accurate. Do you really think the science channel would show a show that is not 'very good'? Of course, it is controverisal, no one really knows for sure -- because no one can prove it. But they mentioned it was highly inprobably as well.

You sound like you do not have a very good understanding of things like quantum physics so I'm not sure how valid your assertation of "quite accurate" is. The discovery channel has shown inaccurate shows before from what I've heard on this forum.

 

[TheStatutoryApe]

Actually, on Discovery channel and the science channel, they have several about time travel and quantum physics. It was merely to illustrate a point. The point was, as I recall, that if you COULD go faster thant he speed of light you would theortically go backwards in time. Of course, nothing can go faster than Light (C) but it was just an EXAMPLE.
The show was actually quite accurate. Do you really think the science channel would show a show that is not 'very good'? Of course, it is controverisal, no one really knows for sure -- because no one can prove it. But they mentioned it was highly inprobably as well.

From what I remember of the show it really glossed over most details to where I wasn't even sure exactly what they were getting at in many instances. Even when they were discussing relativity I had no idea how they were making the jumps in logic they were. So no I don't think it was very accurate because they didn't even describe their material in a comprehensible manner. Compilation of odd scientific phenomena and huge leaps in logic are what junk science is made of. You should listen to Coast to Coast so you can get a handle on how to identify crack pot ideas.
Travel beyond the speed of light, possible or not, does not necessarily mean traveling through time as far as I understand. Aside from theory the only thing that comes even close to supporting this was when they had a photon(?I think?) located in two places at the same time for a small fraction of a second.
I've yet to ever hear a logical explination on how time travel is possible. The closest thing is the worm hole theory and I think that even that has several problems with it. Perhaps the closest thing to time travel is just a sort of bending of "spacetime".

 

[ZapperZ]

The show was actually quite accurate. Do you really think the science channel would show a show that is not 'very good'? Of course, it is controverisal, no one really knows for sure -- because no one can prove it. But they mentioned it was highly inprobably as well.

1. How can you judge if the show was "quite accurate" when you yourself have admitted that you haven't learned that much physics yet?

2. The Discovery channel has had shows about ghosts and paranormal events. Enough said.

I hate to think that these are you primary sources of knowledge to justify your claims on here. I thought people are wise enough to know that we demand better quality of sources on here?

Zz.

 

[ZapperZ]

Thank you! This is what I was trying to say!
What I mean't was, this program was credible! It also had one of the few pioneers int ime travel, Kip. Also, it was on the science channel (By discovery) Everything on there is fact. There was also one on quantum physics abuot what is light, a wave or a particle? It is both. I learned so much. It is great
What i meant was, as someone else mentioned, we caused subatomic particles to go 99.999999999% the speed of light. This is what I meant. they encoded these on a music lase beam, and sent them across the room. It didn't go anywhere, but it was cool and they were able to get the speed. In fact, they said it went 2x the speed of light. You may not believe it, i just wish i wouldve written down the names..

I think this just illustrated what I just posted. You have to be VERY careful on establishing what you are seeing from these shows especially considering you do not have the background to properly interpret these things.

The apparent superluminal speeds here, I'm guessing, came from a "tunneling" experiment. And as in any TV shows, they didn't tell you the details, nor did they tell you the OTHER side of the story. This superluminal claim is highly controversial. If you had bothered to look at the list of evidence for the postulate of Special Relativity in my journal, you would have seen at least a couple of entries on this particular claim. The superluminal claim is neither accepted, nor has been verified. In fact, there have been theoretical description that the SIGNAL velocity was in fact below c in such experiments!

You cannot use "TV shows" as sources to back up your physics arguments, especially when you haven't fully understood the fundamentals. Physics is not done this way. Use these TV shows for what they're meant - as a "fable" for the general public to get a brief flavor of physics. They are NOT meant to TEACH physics.

As Integral has said, there is a difference between learning physics, and learning ABOUT physics. I think you have confused the latter with the former.

Zz.

 

[FredGarvin]

Do you really think the science channel would show a show that is not 'very good'? Of course, it is controverisal, no one really knows for sure -- because no one can prove it. But they mentioned it was highly inprobably as well.

I have seen quite a bit of, well, crap for lack of a better word, come out of the Discovery Channel and the like.

 

[zoobyshoe]

Travel beyond the speed of light, possible or not, does not necessarily mean traveling through time as far as I understand.

Around the time of the Einstein Centenial (late 1970s) a lot of magazines were quoting Einstein, and particularly quoting anything he said that seemed to suggest strange things were possible.

I think I read back then that Einstein said that if we could exceed the speed of light and catch up to light that had relfected off the Earth ages ago, we'd be able to "see" the Earth's past.

This is akin to realizing that looking at the sun is to receive 8 minute old information, or that looking at a particular star might mean we're seeing hundred thousand year old information.

This may be where the notion that faster-than-light travel means going back in time comes from. It would be a misunderstanding of this.

 

[Ivan Seeking]

As noted, that's a pretty rediculous statement considering I'm sure he'd seen birds before. But perhaps he was talking about technology, not science...?

Something akin to saying that we could never generate enough energy to significantly warp spacetime, perhaps.

 

[Ivan Seeking]

The thing that gets me is that we find so much prognostication over an imcomplete theory; or really, two. Now how scientific is that?

 

[QuantumTheory]

I hate to think that these are you primary sources of knowledge to justify your claims on here. I thought people are wise enough to know that we demand better quality of sources on here?
Zz.

What you said, is the kind of crap I can't stand. Dude, I'm 17. No, I haven't TAKEN a physics class, so I may not UNDERSTAND the 'fundamentals' of physics. In fact, I just graduated high school. I am very good at math, but before high school I wasn't. I became very good and loved math in high school. The farthest I've gotten in school was some algebra (Didnt get to quadratics or factoring that welll, or paraboles), most f geomtetry, but i never took trig, pre calc, or calc. So naturally, I can't do physics without knowing calc, I don't think?

Just so you know, I do know a lot of properties of physics. I do understand the fundamentals of special relativity, relativity, some quantum mechanics, although I do not know the mathemathics behind it, so you can say I "dont know it", whatever. I do know a lot about the shrtonnger cat I believe it was demonstrating the cat as 'alive and dead'a t the same time or that a photon is both a particle and a wave.

I also understand inertia as well. I believe it is when you are traveling in a car, and you stop with the brakes, and you do not have a seat belt you, you can feel your body moving forward. I believe this is due to 2 forces: 1) Gravity. 2) Ineria. Newtons theory says that an actoin will have an opposote and equal reaction, therefore, when you stop, you are moving forward at the same speed the car was going the instanteous moment before it stopped. I may be wrong here, but dude, give me a break. I'm fricking 17.

Sorry, if it wasn't accurate, by he way. I didn't know this. Yeah, I can' bieleve discovery would have shows on ghosts, but come on. I was just wondering if time travel as theortically possible, that's all. But you get on my case because it isn't 'propery material'. I am interested in physics, and I do understand a lot of it.

However, I do not appreciate you trying to argue with me. I'd appreciate it if you'd tell me what to correct, etc. But it's useless to argue with me. Why? Because I probably am wrong at things, you've taken physics, I haven't. And you're most likely not as young as me, therefore have more knowledge

Also, please don't say I don't know a lot for my age. I have a feeling you'e going to say "You don't know much for your age." , most teens know a lot more about physics than you. This doesn't help the situation.

Thanks

 

[ZapperZ]

What you said, is the kind of crap I can't stand. Dude, I'm 17. No, I haven't TAKEN a physics class, so I may not UNDERSTAND the 'fundamentals' of physics. In fact, I just graduated high school. I am very good at math, but before high school I wasn't. I became very good and loved math in high school. The farthest I've gotten in school was some algebra (Didnt get to quadratics or factoring that welll, or paraboles), most f geomtetry, but i never took trig, pre calc, or calc. So naturally, I can't do physics without knowing calc, I don't think?
Just so you know, I do know a lot of properties of physics. I do understand the fundamentals of special relativity, relativity, some quantum mechanics, although I do not know the mathemathics behind it, so you can say I "dont know it", whatever. I do know a lot about the shrtonnger cat I believe it was demonstrating the cat as 'alive and dead'a t the same time or that a photon is both a particle and a wave.
I also understand inertia as well. I believe it is when you are traveling in a car, and you stop with the brakes, and you do not have a seat belt you, you can feel your body moving forward. I believe this is due to 2 forces: 1) Gravity. 2) Ineria. Newtons theory says that an actoin will have an opposote and equal reaction, therefore, when you stop, you are moving forward at the same speed the car was going the instanteous moment before it stopped. I may be wrong here, but dude, give me a break. I'm fricking 17.
Sorry, if it wasn't accurate, by he way. I didn't know this. Yeah, I can' bieleve discovery would have shows on ghosts, but come on. I was just wondering if time travel as theortically possible, that's all. But you get on my case because it isn't 'propery material'. I am interested in physics, and I do understand a lot of it.
However, I do not appreciate you trying to argue with me. I'd appreciate it if you'd tell me what to correct, etc. But it's useless to argue with me. Why? Because I probably am wrong at things, you've taken physics, I haven't. And you're most likely not as young as me, therefore have more knowledge
Also, please don't say I don't know a lot for my age. I have a feeling you'e going to say "You don't know much for your age." , most teens know a lot more about physics than you. This doesn't help the situation.
Thanks

Oh, so now you're psychic also?

Note that I have never mentioned anything about your age? What does THAT have anything to do with anything?

And you still have no clue when I said that there's a difference between learning physics, and learning ABOUT physics. You got the latter, not the former. This is not physics. All you got was similar to receiving a description through 2nd hand channels about the color "blue" without ever seeing the color itself.

Time travel? Based on our current understanding, there is no such thing. Is it possible ever for human beings? Based on our current understanding, no human can survive such a thing.

I thought this answer was given WAY early in this thread already! Now does this put this idea to rest finally?

Zz.

 

[Pengwuino]

Quantum, you need to give everyone a break here, people here know a LOT about physics including the mathematics behind it all. I mean god knows how many phd's are on this board!

What you are basically saying is that you want someone to agree with you and no one can really do it. When you say you "understand physics" but then say you have absolutely no mathematical understanding of it, it's like saying you know how a car works because you press the accelerator and it moves but then ask "why can't my car be totally silent, go 400,000mpg and travel 80000mph using water as a fuel!".