Why can't we reach to Speed of light at Space?

In summary, the limitations on traveling at ultra high speeds are the increased mass and the difficulty in generating enough thrust.
  • #1
Majid1986
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1
a question has made my mind busy...it is told that there is no frictions at space...frictions of air...friction of gravity and etc...none of these does exist in the space (outside the earth)...so we can launch a spacecraft with a primary speed(orbit speed of earth) and equip it with a engine...with a primary speed , and with a engine , and without any friction...theorically we can increase the speed and acceleration...and then reach to a ultra high speed until a speed like light speed...but WHAT IS THE LIMITATIONS?
 
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  • #2
The problem is that as the speed of an object increases so does the mass at normal speeds this is pretty insignificant but as yuo approach the speed of light the mass of the object approaches infinity.
 
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  • #3
Majid1986 said:
a question has made my mind busy...it is told that there is no frictions at space...frictions of air...friction of gravity and etc...none of these does exist in the space (outside the earth)...so we can launch a spacecraft with a primary speed(orbit speed of earth) and equip it with a engine...with a primary speed , and with a engine , and without any friction...theorically we can increase the speed and acceleration...and then reach to a ultra high speed until a speed like light speed...but WHAT IS THE LIMITATIONS?

You don't have to go into outer space, nor do you need to consider something as big as a spacecraft . Just look at what is happening at particle accelerators around the world. The LHC can only get the protons to 0.999c traveling inside the vacuum pipes. If something that small (when compared to your spacecraft ) inside a vacuum line required such huge amount of energy to "just" get to that speed, how much more of an effort do you think it will take to do the same on your spacecraft ?

There are a lot of things you can learn from things we already know here on Earth.

Zz.
 
  • #4
Jobrag said:
The problem is that as the speed of an object increases so does the mass at normal speeds this is pretty insignificant but as yuo approach the speed of light the mass of the object approaches infinity.
Not really. It has the energy equivalent of increased mass but not an increase in actual mass.

Think about it this way: An object traveling at .999c relative to the Earth is also traveling at .8c relative to some other frame of reference and .1c to yet another and very slowly relative to something traveling almost along-side it. If the object actually had some mass based on it's speed relative to Earth, it would have to have different masses relative to each of those other frames of reference. Now you can't have the same object having different inherent masses, thus, clearly, the object itself does not have any increase in mass.

This concept of "relativistic mass" has long been deprecated in Physics, it's just that the word hasn't yet gotten to pop-sci writers.
 
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  • #5
In rocket propulsion, matter is forcefully ejected from the engine, producing an equal and opposite reaction. Under Newtons 3rd law, it appears rocket velocity cannot exceed its exhaust velocity, but, the exhaust velocity of a LOX/H2 rocket [used to launch satellites] is only 15,000 mph whereas Earth's escape velocity is 17,500 mph. Tsiolkovsky, legendary rocketry expert, worked out the math in 1903. [tex] \Delta v = v_e \ln \frac{m_0}{m_1} [/tex].
846f53c9f23cb561a8abb3a71fea4eba.png
= initial mass
b76530f37a5cbc3d17ebe8df6fed402f.png
= final mass [
846f53c9f23cb561a8abb3a71fea4eba.png
less expended mass - i.e. fuel and boosters]
a4428fdd20c2aad78733b5847efb8bd9.png
= rocket exhaust velocity
090f92439b671c9f0666f3d1d13dd30c.png
= maximum change in rocket velocity - assuming no external forces

Even putting relativistic corrections aside, you would need stupendous exhaust velocity to achieve anything close to relativistic velocities.
 
  • #6
I don't really like any of the answers (sorry). Based on the premise of the question (the total irrelevancy of friction), it doesn't appear the OP even understands Newton's laws. In that context, the critical reason our real rockets can't get anywhere close to C is f=ma and the fact that rockets have to carry a lot of fuel to generate thrust. So they can't accelerate very fast or for very long. Different propulsion technologies, such as nuclear fuel, may result in much more efficient and therefore much faster rockets, but nothing on the horizon even gets us close to where Relativity matters.

Chronos, your answer in particular is very confusing. It implies a conflict due to the speed of the rocket exceeding the speed of the exhaust. This isn't the case. They are not tied to each other in any direct way -- that's why the rocket speed isn't in the equation. Getting a rocket to move much, much faster than its exhaust velocity can be done by firing the rocket for a long time and using multiple stages -- which would be similar to just arbitrarily changing reference frames (such as from Earth stationary to milky-way stationary). The (Galilean) principle of Relativity demands that acceleration is independent of reference frame.
 
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  • #7
As you approach the speed of light your mass increases and slows you down, and with more energy you have more mass (E=mc2) so you would never actually approach the speed of light.
 
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  • #8
Russ. Are you disputing the Tsiolkovsky equation, or what? I don't get it.
 
  • #9
Quds Akbar said:
As you approach the speed of light your mass increases and slows you down, and with more energy you have more mass (E=mc2) so you would never actually approach the speed of light.
When responding in a thread, it is a good idea to read the other responses before you respond, so you can be sure you are not simply saying the same thing over again or even worse, as in your case, continuing to provide incorrect information. Please read post #4
 
  • #10
Chronos said:
Russ. Are you disputing the Tsiolkovsky equation, or what? I don't get it.
No, certainly not. I was disputing something implied by your description/application of it: that rockets are typically limited to roughly the speed of their exhaust.
 
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  • #12
Majid1986 said:
a question has made my mind busy...it is told that there is no frictions at space...frictions of air...friction of gravity and etc...none of these does exist in the space (outside the earth)...so we can launch a spacecraft with a primary speed(orbit speed of earth) and equip it with a engine...with a primary speed , and with a engine , and without any friction...theorically we can increase the speed and acceleration...and then reach to a ultra high speed until a speed like light speed...but WHAT IS THE LIMITATIONS?
I will not pretend that I am an expert, but I do know that the laws of physics break down at that speed correct?
 
  • #13
stehfahknee said:
I will not pretend that I am an expert, but I do know that the laws of physics break down at that speed correct?
No, absolutely not. The laws of physics are quite clear about what happens. Please read the other responses in this thread.
 
  • #14
I have. Many disputes mostly and no way to know who is correct or incorrect. Which means more research to learn, but that's actually a good thing.
I have always read that when you reach the speed of light things get weird.
I'm off to read some more then.
 
  • #15
stehfahknee said:
I have. Many disputes mostly and no way to know who is correct or incorrect.
There is no dispute. Special relativity is extremely well-studied, and well-understood.
That is not to say it is not difficult to describe in few words - as we are seeing here.

stehfahknee said:
I have always read that when you reach the speed of light things get weird.
Weird is subjective.
It is certainly very different from our usual day-to-day experiences, but it quite faithfully obeys our laws of physics.
 
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  • #16
DaveC426913 said:
There is no dispute. Special relativity is extremely well-studied, and well-understood.
That is not to say it is not difficult to describe in few words - as we are seeing here.
... seems argumentative to me, but that may just be the norm, I just started on here. Never really did blogs before, so you could be right.

Weird is subjective.
It is certainly very different from our usual day-to-day experiences, but it quite faithfully obeys our laws of physics.
You have a point. I'm reading up on it now, and getting pretty into it. Which means I will probably be preoccupied for the next...well... who knows how long... I tend to start reading about one thing, see something mentioned and go off on that branch, which leads to another and so on and so on. I can stay up for days on these tangents...
 
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  • #17
Chronos said:
russ_watters said:
I was disputing something implied by your description/application of it: that rockets are typically limited to roughly the speed of their exhaust.
Maximum rocket velocity is limited by, but, not to exhaust velocity. According to NASA, maximum rocket velocity is twice its exhaust velocity - re: http://www.hq.nasa.gov/pao/History/SP-4026/noord12.html. Another interesting link is http://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html
The first link is, to use Russ Waters' words, rough. There's nothing there that I can see that says maximum rocket velocity is twice its exhaust velocity. That is not the case. If it was, we wouldn't be able to vehicles into orbit. The best specific impulse fuel that is capable of launching a vehicle into orbit is liquid hydrogen as propellant and liquid oxygen as oxidizer. This has a vacuum exhaust velocity of 4.4 to 4.5 km/s. Performance in an atmosphere is less than that. Double that and you get at most 9 km/s. Getting into low Earth orbit requires 10 to 11 km/s delta V. Escaping the Earth's gravitational field from the surface of the Earth takes roughly twice that.

Given that, how do we send vehicles into orbit, and then towards other planets? (That's a rhetorical question.)

The answer is that a factor of two isn't quite right. A single stage rocket whose initial mass is 90% fuel will achieve 2.3 times the exhaust velocity, which is already over your limit of twice the exhaust velocity. That's something even amateur rocketeers can accomplish. A single stage rocket whose initial mass is 95% fuel will achieve 3 times the exhaust velocity. This still doesn't get a vehicle to the ~20 km/s Δv needed to escape the Earth's gravitational field. The solution is simple: Don't use a single stage rocket. For example, the Saturn V+Apollo vehicle used to take astronauts to the Moon and back was essentially a six stage rocket. (Note well: Nobody has made a six stage rocket since Apollo was cancelled.)Nonetheless, what Russ wrote was essentially correct. He said "roughly". Rockets are indeed roughly limited by the speed of their exhaust (to within an order of magnitude).Getting back to the original question,
Majid1986 said:
WHAT IS THE LIMITATIONS?
Aside: I'm being nitpicky here, but it's "what **are** the limitations," not "what is the limitations." You are posting from an English-speaking country. You should know the rules. Use them.

The ideal rocket equation establishes one of the limitations. Making a vehicle that is 99% fuel is an engineering impossibility. Even if we could make such a vehicle, the Δv would only be 4.6 times the exhaust velocity. Play games with making a multistage vehicle and you might get another factor of 3 or so on top of that. You would need a vehicle whose exhaust velocity is beyond anything achievable or imaginable, and you still wouldn't get anywhere close to the speed of light. The amount of energy needed to make a tiny proton get close to the speed of light is immense. The amount of energy needed to make a decent-sized spacecraft get close to the speed of light is beyond immense. A decade's worth of the world's entire energy output might do the trick.

Even then, there are other problems. Suppose our children's children's children do find some magic that enables a spacecraft to 90% of the speed of light. Space is not quite empty. There's gas and dust in interstellar space, and this will slow them down (a lot). Interstellar space also contains other occasional obstacles. At 90% the speed of light, a collision with a tiny one gram chunk of stuff would unleash the equivalent of multiple nuclear bombs worth of energy on the spacecraft .
 
  • #18
thanks all...but none of you friends understood my question...
lets give you a clearance about what is across my mind...first i am not from an english country and miss-spelling may occur in my post...i have a basic information about physics and not involved with equations and formulas
second
suppose we launch a spacecraft with primary speed (for example 1000km/h or mils/h)...in the space where no friction exists, we turn the engine ON and naturally the speed must be increased as in our example to 1100 km/h...we turn the engine OFF...now the speed must be 1100km/h...after a while we turn the engine ON and our speed reaches to 1200km/h...we turn the engine OFF...turn it ON again and so on...we continue this manner for 1 year...2 years..3 years and more(suppose our spacecraft has enough fuel to last all the years)...after many years theorically we must reach to the speed of light...but why we can't reach? this is my question...
 
  • #19
To quote from http://www.hq.nasa.gov/pao/History/SP-4026/noord12.html

"... If the v/c ratio becomes greater than 1 (the travel velocity exceeds the velocity of expulsion), the efficiency of the reaction is diminished again and, finally, for v/c=2 it again goes through zero and even becomes negative (at travel velocities more than twice as large as the velocity of expulsion).

The latter appears paradoxical at first glance because the vehicle gains a travel velocity as a result of expulsion and apparently gains a kinetic force as a result! Since the loss of energy, resulting through the separation of the expulsion mass loaded very heavily with a kinetic force due to the large travel velocity, now exceeds the energy gain realized by the expulsion, an energy loss nevertheless results for the vehicle from the entire process despite the velocity increase of the vehicle caused as a result. The energy loss is expressed mathematically by the negative sign of the efficiency. Nonetheless, these efficiencies resulting for large values of the v/c ratio have, in reality, only a more or less theoretical value.

It can, however, clearly and distinctly be seen from the table how advantageous and, therefore, important it is that the travel velocity approaches as much as possible that of the expulsion in order to achieve a good efficiency of reaction, but slight differences (even up to v=0.5 c and/or v=1.5 c) are, nevertheless, not too important because fluctuations of the efficiency near its maximum are fairly slight. Accordingly, it can be stated that the optimum travel velocity of a rocket vehicle is approximately between onehalf and one and onehalf times its velocity of expulsion."

Thus, v/c = 2 is not asserted as an absolute limit on rocket velocity. The exhaust velocity of LOX/LH rocket is approximately 15,000 mph and escape velocity of Earth is about 25,000 mph. So, achieving escape velocity is within v/c=2. From http://www.nasa.gov/mission_pages/station/expeditions/expedition30/tryanny.html it is noted

" If the radius of our planet were larger, there could be a point at which an Earth escaping rocket could not be built. Let us assume that building a rocket at 96% propellant (4% rocket), currently the limit for just the Shuttle External Tank, is the practical limit for launch vehicle engineering. Let us also choose hydrogen-oxygen, the most energetic chemical propellant known and currently capable of use in a human rated rocket engine. By plugging these numbers into the rocket equation, we can transform the calculated escape velocity into its equivalent planetary radius. That radius would be about 9680 kilometers (Earth is 6670 km). If our planet was 50% larger in diameter, we would not be able to venture into space, at least using rockets for transport. "

Assuming a proportionate mass increase, escape velocity would increase to about 36,000 mph at r = 9680 km, which exceeds v/c = 2. I therefore concluded v/c = 2 was reasonably correct.
 
  • #20
Majid, using the Tsiolkovsky equation, and assuming your rocket has a realistic fuel to payload mass ratio of 24 to 1 [96% fuel], you could never increase rocket velocity to more than about 3.17 times the fuel exhaust velocity. So, even ignoring relativistic corrections, you need stupendous exhaust velocity to rocket your way even remotely near light speed. Even with a ludicrous fuel to payload mass ratio of 9999 to 1 [99.99% fuel] you would still only add about 9.21 times fuel exhaust velocity to your rocket. An ion thruster, the most powerful known rocket engine, is only capable of achieving around 200,000 mph exhaust velocity - which is still a very long way from light speed. At some point you must make a concession to the material science gods and worry about what kind of exhaust velocity can be tolerated by the material employed by your chosen rocket design. It is generally agreed that interstellar travel via rocket propulsion is a fail.
 
  • #21
Chronos, you missed my point. DH picked-up on the issue, but maybe you didn't see it there:
DH said:
A single stage rocket whose initial mass is 90% fuel will achieve 2.3 times the exhaust velocity, which is already over your limit of twice the exhaust velocity. That's something even amateur rocketeers can accomplish. A single stage rocket whose initial mass is 95% fuel will achieve 3 times the exhaust velocity. This still doesn't get a vehicle to the ~20 km/s Δv needed to escape the Earth's gravitational field. The solution is simple: Don't use a single stage rocket. For example, the Saturn V+Apollo vehicle used to take astronauts to the Moon and back was essentially a six stage rocket.
Whether the Δv value is 2 or 2.3 or 3.0 for a single stage rocket mostly misses my point. My point was that using a multi-stage rocket you essentially reset the rest frame of the rocket and therefore the reset the velocity used in the rocket equation to zero at the start of every next stage. There are, of course, practical considerations to how big you can make a self-supporting rocket (of course, assembling it in space would help...), but using multi-stage rockets enables velocities relative to the starting point on Earth of much greater than a factor of 2 or 3.
DH said:
Nonetheless, what Russ wrote was essentially correct. He said "roughly". Rockets are indeed roughly limited by the speed of their exhaust (to within an order of magnitude).
Er, well, thanks, but that's actually not what I said/meant, that's what Chronos implied (as I read it). I said they are not limited by/to the speed of their exhaust or twice the speed of their exhaust. I don't want to get into an argument about what "roughly" means, but whether it is 5x or 15x, IMO, that's not all that close to the speed of the exhaust. I wanted to clarify this (apparently I failed badly) because there is a common misconception that people have that in order to propel a rocket in one direction, the propelled mass has to travel in the opposite direction, relative to the starting reference frame. People don't recognize that the propelled mass can be traveling away from the starting point while still providing thrust. Random citation:
Yahoo Answers said:
I've bumped into a few people over the years who are absolutely convinced that the maximum speed a rocket can achieve is equal to the speed of its exhaust gases.

Where do you suppose this misconception comes form?
https://answers.yahoo.com/question/index?qid=20080110163908AANigzX

I will say, though, that looking at the numbers, they are lower than I would have expected. I am interested in what is reasonably achievable -- Apollo isn't a great example, because it included multiple spacecraft , fuel for a landing and other bulky cargo (people and life support). I'm curious if you could guestimate how much how much delta-V a Saturn V could provide to a small probe...maybe I should try, for the exercise...
 
  • #22
Later I may run a scenario to estimate what we could achieve with currently available rockets if we really, really wanted to, but looking-into what we've done so far, it looks like the New Horizons probe had the highest initial velocity, at 16.26 km/sec. Googling, someone else asked a similar question regarding the Saturn V and got a limit 18 km/sec for the 3 main stages, without payload (not including the Apollo spacecraft ). That's 4:1.
 
  • #23
But the OP is back:
Majid1986 said:
suppose we launch a spacecraft with primary speed (for example 1000km/h or mils/h)...in the space where no friction exists, we turn the engine ON and naturally the speed must be increased as in our example to 1100 km/h...we turn the engine OFF...now the speed must be 1100km/h...after a while we turn the engine ON and our speed reaches to 1200km/h...we turn the engine OFF...turn it ON again and so on...we continue this manner for 1 year...2 years..3 years and more(suppose our spacecraft has enough fuel to last all the years)...after many years theorically we must reach to the speed of light...but why we can't reach? this is my question...
So I was at least partly wrong in my interpretation of this: it can be interpreted as a Relativity question. We just had a detailed discussion of fuel and thrust in real rockets, but if fuel is not an issue -- say, if we used a laser-propelled rocket or solar sail* -- Relativity still eventually becomes an issue.

Others already answered this, but if you want something more succinct: as your speed rises, the amount of acceleration you get for the same force drops (as viewed from the frame of reference of the place where you launched from).

But there's a nice side-benefit to Relativity: from your reference frame, space seems to shrink as you accelerate, so you actually can get to a place far a way in a reasonable amount of time as read from your clock -- it's just that when you get home, you'll find all your friends and family have been dead for a very long time.

*Of course, there's probably also a "rocket equation" for laser propulsion or solar sails due to redshift of the light.
 
  • #24
Russ, I agree. Upon further consideration, staged rocket terminal velocity merely resets initial velocity for the next stage in the Tsiolkovsky equation, as you noted. The NASA articles I cited merely constrain velocity based on technological considerations. So, the theoretical answer to the op question is ... it depends [as attorney's are won't to contend]. I do, however, feel the v/c = 2 limit is essentially valid. The greatest velocity ever achieved by rocket propulsion is about 36,000 mph - re http://blogs.scientificamerican.com/life-unbounded/2013/02/25/the-fastest- spacecraft -ever/.
 
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  • #25
What has not been mentioned yet is that fact that as a particle is accelerated near the speed of light it begins to emit radiation in the form of light. Thus, there is a loss of energy that increases with speed.
 
  • #26
I think Majid is not asking about rocket science, but about why anything with a mass cannot reach the speed of light. That is, why there is a physical restriction to reach such speed. And I always thought it had to do with E=mc², not exhaust velocity or what not (which is an initial restriction, but not the ultimate restriction).
 
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  • #27
Please notice that the exhaust gas velocity is measured with respect to the rocket (whatever speed the rocket has). That is if the rocket has a velocity of C/2 upward with respect to an observer, the exhaust gas speed is (C/2-exhaust speed) upward. This always accelerates the rocket.
As Chronos mentioned at #24, laser propulsion or sailing may be used in reply to those who raise the question of fuel for this thought experiment. Remember that light always hits the rocket at speed C and transfers some momentum to it.
The question may be repeated in this way: The person who rides the rocket is stationary with respect to the rocket and do not measure any change in mass or change in his clock rate, and he feels and measures a continuous acceleration. So integrating over time he calculates his speed which is ever increasing and has no limit.
Of course other observers have different observations.
 
  • #28
Consider it a different way. Given we invent some new, infinite source of energy, how would we get YOU even close to the speed of light? Because you are so extremely fragile, you can only tolerate so much acceleration. So, it will take more than your lifetime just to get you up to a fraction of the speed of light without squishing you into a thin paste. Then there's the time it would take to decelerate you before you reached your destination. Inertia is a huge limiting factor to the use of any current form of propulsion or most any material or technology we have. In order for you to actually explore the stars just in our neighborhood, you would have to either invent a way to live an extremely long time or find an entirely different way to transverse space that doesn't require acceleration. Warp Drive is an invention of science fiction. We currently have the slightest of hints that space can be warped. Perhaps a thousand years from now, someone will find a way. Or, maybe not.
 
  • #29
Assume you ride a spaceship which has a constant small acceleration of 1g. Inside this rocket you feel the same as you feel your weight on earth.
With this constant acceleration you will reach (and pass) the speed of light in few years and will be able to return home before getting old.
 
  • #30
You could create fuel via Solar or via magnetism from passing whatever or temperature chage. etc...

One Limitation, is that sooner or later you will bump into something; and you cannot turn mass (to miss objects such as space rocks) at very high velocity. And in an infinite universe with an equally infinite `Proportion` of matter in it, you will eventually bump into something in every direction. It may be part of the reason why the Universe appears slightly darker in places.Also; as the Universe/s have Matter in them; then there is the innate friction which that is an example of. Gas would be another.If you want to send something quickly somewhere; you would be better putting a double barrel gun in space which will sent two objects in opposite directions when you fire it. Idea 6,013.
 
  • #31
K. Hamze said:
Assume you ride a spaceship which has a constant small acceleration of 1g. Inside this rocket you feel the same as you feel your weight on earth.
With this constant acceleration you will reach (and pass) the speed of light in few years and will be able to return home before getting old.

Not this tired old argument.

You cannot `go back in time`; as time is a measuring stick (and just like the `temperature` of `something measured` is not altered by changing the numbers on the side of the gauge); and as its only as tangible as a shadow.

You would also have to reverse every atom of the universe at the same time; for it to be truly as though going back in time. You have more likelihood of slowing down time by stopping atoms moving.

Be realistic sometimes.
 
  • #32
Snerdguy said:
Consider it a different way. Given we invent some new, infinite source of energy, how would we get YOU even close to the speed of light? Because you are so extremely fragile, you can only tolerate so much acceleration. So, it will take more than your lifetime just to get you up to a fraction of the speed of light without squishing you into a thin paste. Then there's the time it would take to decelerate you before you reached your destination. Inertia is a huge limiting factor to the use of any current form of propulsion or most any material or technology we have. In order for you to actually explore the stars just in our neighborhood, you would have to either invent a way to live an extremely long time or find an entirely different way to transverse space that doesn't require acceleration. Warp Drive is an invention of science fiction. We currently have the slightest of hints that space can be warped. Perhaps a thousand years from now, someone will find a way. Or, maybe not.

What you suggest is not the problem. You can create conditions in which velocity does not effect matter within a defined space. If you know what you are doing.
 
  • #33
guywithdoubts said:
I think Majid is not asking about rocket science, but about why anything with a mass cannot reach the speed of light. That is, why there is a physical restriction to reach such speed. And I always thought it had to do with E=mc², not exhaust velocity or what not (which is an initial restriction, but not the ultimate restriction).
I think you are right , what the OP asked is that , if any object( spacecraft in this case) is accelerated continuously in space without running out of fuel , why can't that object reach or exceed the speed of light ?

I found this when I googled http://physics.about.com/od/relativisticmechanics/f/SpeedofLight.htm
So, according to this link , you can travel at the speed of light but you will need infinite amount of energy to do so.

The universe itself has finite amount of energy (first law of thermodynamics) hence you can't travel at the speed of light.
I hope someone with a background in this subject validates the information in this link.
 
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  • #34
Monsterboy said:
I found this when I googled http://physics.about.com/od/relativisticmechanics/f/SpeedofLight.htm
So, according to this link , you can travel at the speed of light but you will need infinite amount of energy to do so.
That would better be interpreted as "because there is no such thing as an infinite amount of energy, objects with mass cannot travel at the speed of light".
 
  • #35
When I was trying to understand why the speed of light couldn't be reached (except by light itself, which is unique by traveling in space but never in time), what helped me was a drawing of the hyperbola, a geometric curve that I'm sure Wikipedia describes pretty well. The curve starts out almost as well-rounded as a circle, but gradually flattens out until it's very nearly a straight line. However, it never actually becomes a straight line, even at infinity. With some unknown propulsion system, some sort of spaceship might hypothetically come EXTREMELY close to the speed of light, but, like the perfectly straight line that you might wish that NEARLY-flat curve would become, it can NEVER get there.

For related reasons, hyperbolae are common in two-dimensional representations of the multiverse: Some good examples are on the site "Next Step Infinity".
 
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<h2>1. Why is the speed of light considered the maximum speed in space?</h2><p>The speed of light, which is approximately 299,792,458 meters per second, is considered the maximum speed in space because it is the fundamental speed limit of the universe. This is based on Einstein's theory of relativity, which states that the speed of light is a constant and cannot be exceeded by any object or particle. As an object approaches the speed of light, it becomes increasingly difficult to accelerate it further, and it would require an infinite amount of energy to reach the speed of light.</p><h2>2. Can anything travel faster than the speed of light?</h2><p>Based on our current understanding of physics, it is not possible for anything to travel faster than the speed of light. As mentioned before, the speed of light is considered the fundamental speed limit of the universe, and it would require an infinite amount of energy to reach or exceed it. Additionally, as an object approaches the speed of light, its mass increases, making it even more difficult to accelerate further.</p><h2>3. Why is it important to understand the limitations of the speed of light in space?</h2><p>Understanding the limitations of the speed of light in space is crucial for many aspects of science and technology. It helps us understand the behavior of objects and particles in the universe, and it has significant implications for space travel and communication. It also plays a crucial role in the development of theories and models in physics, such as general relativity and quantum mechanics.</p><h2>4. Is it possible to travel close to the speed of light in space?</h2><p>While it is not possible to reach the speed of light, it is possible to travel close to it. In fact, spacecraft like the Voyager 1 and 2 have achieved speeds of over 17 kilometers per second, which is about 0.0057% of the speed of light. However, as an object approaches the speed of light, the effects of time dilation and length contraction become more significant, making it challenging to travel at such high speeds.</p><h2>5. Are there any exceptions to the speed of light being the maximum speed in space?</h2><p>There are a few exceptions to the speed of light being the maximum speed in space, but they are still within the realm of Einstein's theory of relativity. For example, the expansion of the universe can cause objects to move away from each other at speeds faster than the speed of light, but this is due to the expansion of space itself and not the object's actual speed. Another exception is the hypothetical concept of wormholes, which could potentially allow for faster-than-light travel, but it is still purely theoretical and has not been proven to exist.</p>

1. Why is the speed of light considered the maximum speed in space?

The speed of light, which is approximately 299,792,458 meters per second, is considered the maximum speed in space because it is the fundamental speed limit of the universe. This is based on Einstein's theory of relativity, which states that the speed of light is a constant and cannot be exceeded by any object or particle. As an object approaches the speed of light, it becomes increasingly difficult to accelerate it further, and it would require an infinite amount of energy to reach the speed of light.

2. Can anything travel faster than the speed of light?

Based on our current understanding of physics, it is not possible for anything to travel faster than the speed of light. As mentioned before, the speed of light is considered the fundamental speed limit of the universe, and it would require an infinite amount of energy to reach or exceed it. Additionally, as an object approaches the speed of light, its mass increases, making it even more difficult to accelerate further.

3. Why is it important to understand the limitations of the speed of light in space?

Understanding the limitations of the speed of light in space is crucial for many aspects of science and technology. It helps us understand the behavior of objects and particles in the universe, and it has significant implications for space travel and communication. It also plays a crucial role in the development of theories and models in physics, such as general relativity and quantum mechanics.

4. Is it possible to travel close to the speed of light in space?

While it is not possible to reach the speed of light, it is possible to travel close to it. In fact, spacecraft like the Voyager 1 and 2 have achieved speeds of over 17 kilometers per second, which is about 0.0057% of the speed of light. However, as an object approaches the speed of light, the effects of time dilation and length contraction become more significant, making it challenging to travel at such high speeds.

5. Are there any exceptions to the speed of light being the maximum speed in space?

There are a few exceptions to the speed of light being the maximum speed in space, but they are still within the realm of Einstein's theory of relativity. For example, the expansion of the universe can cause objects to move away from each other at speeds faster than the speed of light, but this is due to the expansion of space itself and not the object's actual speed. Another exception is the hypothetical concept of wormholes, which could potentially allow for faster-than-light travel, but it is still purely theoretical and has not been proven to exist.

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