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Can something move faster than light?


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Poll: Can something move faster than light? (1 member(s) have cast votes)

Can something move faster than light?

  1. Yes (85 votes [58.62%])

    Percentage of vote: 58.62%

  2. No (40 votes [27.59%])

    Percentage of vote: 27.59%

  3. I don't know (20 votes [13.79%])

    Percentage of vote: 13.79%

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#324 Buffy

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Posted 08 August 2007 - 12:06 PM

i know its sounds funny but do u thing that is possible to create something that flyes with speed of light out of the elements fgound on earth. is there any strong metal or aloy that can withsdand it ?

Its not a matter of being "strong enough." The problem is the *amount of energy required* to move something to the speed of light, which according to Einstein is like, totally a lot!

cul8r,
B

#325 ronthepon

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Posted 09 August 2007 - 03:26 AM

i know its sounds funny but do u thing that is possible to create something that flyes with speed of light out of the elements fgound on earth. is there any strong metal or aloy that can withsdand it ?

For an idea, how about some carbon?

You could burn it... :)

#326 riper

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Posted 11 August 2007 - 01:22 PM

i dont think there is any propelant existing that can bust the machine to move with speed of light, and even if there is who will control it? we cant even control 400km/h. the surface of that machine has to be strong enough to withstand the friction against the air particles, unles it is in space. but some russian and german research intitutes are working on it.

#327 Agen

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Posted 12 August 2007 - 05:18 PM

Riper, of course it would take place in space. If it was started on Earth it would move out of the atmosphere in a very-very short time.

In a vacume I don't think it matters how fast you are going to damage the moving object, because there are no obstacles in your way to damage it.

And controllability is not the same thing in space, because balance (like on the road) is not a issue there and there is no wind resistance to deal with.

#328 CraigD

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Posted 12 August 2007 - 05:45 PM

i dont think there is any propelant existing that can bust the machine to move with speed of light …

Riper, I think you may be missing one of the central ideas of this thread: according to the scientific theory best supported by experimental evidence, relativity, no propulsion of any kind can accelerate any machine to the speed of light in vacuum c (exactly 299792458 m/s). This is not because no propellant has enough “muscle”, but because the amount of energy required to do so is infinite. This is due to a phenomena known as mass dilation, or relativistic mass. The formula for the energy Er required by a perfectly efficient mechanical system to accelerate a mass M to speed u, derived from the basic postulates of relativity, is [math]Er = M c^2 \left ( \frac{1}{sqrt{1- \left ( \frac{u}{c} \right )}} -1 \right )[/math]

The non-relativistic, classical mechanical formula for the energy required by a perfectly efficient mechanical system to accelerate a mass to speed u is [math]En = \frac12 M u^2[/math]. If you compare the energy calculated by the 2 different formulae, you’ll see that, for small speeds we ordinarily encounter in vehicles, the 2 energies are nearly the same. As the speed approaches c, however, Er becomes many times greater than En, meaning that the En shouldn’t be used for calculations involving such speeds. Here’s a small table of examples:
Speed u                         Er/En
.0000001 c (car)      108 km/h  1 (not really 1, but too close for my calculator to distinguish)
.0000008 c (plane)    863 km/h  1
.000001 c            1079 km/h  1
.00001 c            10793 km/h  1
.0001 c            107925 km/h  1.0000000074
.0002342 c (*)     252761 km/h  1.00000004113062547
.001 c            1079253 km/h  1.00000075
.00205 c (**)     2212468 km/h  1.000003151885782272
.01 c            10792528 km/h  1.00007500625054
.1 c            107925285 km/h  1.007563051842415
.5 c            539626424 km/h  1.237604307034012232
.9 c            971327564 km/h  3.195450219026216442
.99 c          1068460320 km/h  12.42487919617051118
.999 c         1078173596 km/h  42.81813754120330883
.9999 c        1079144924 km/h  139.4527810654887706
.99999 c       1079242056 km/h  445.2236179659762919
.999999 c      1079251770 km/h  1412.216740358686725
.9999999 c     1079252741 km/h  4470.136960830329925
.99999999 c    1079252838 km/h  14140.1359418890071
.999999999 c   1079252848 km/h  44719.35965061485308
.9999999999 c  1079252849 km/h  141419.3562655933761
The “*” above stands for the fastest manmade vehicles flown to date, the Helios probes. The “**” stands for a hypothetical “dream machine” spacecraft I speculated was possible with present-day technology. Both are discussed in and around the post ‘SR confirming experiments, spacecraft speed records, "dream spacecraft missions"’. I recommend reading its entire thread, “Time dilation does not make sense to me”.

… and even if there is who will control it? we cant even control 400km/h.

Sure we can. Most commercial jet airliners cruise between 800 and 900 km/hr. Geostationary communication satellites orbit at about 11,068 km/hr. The world land speed record, set in 1997 by the ThrustSSC jet powered car, is 763.035 km/hr.

Controlling vehicles has much more to do with minimizing unexpected forces than with the vehicle’s speed. A bicycle going 10 km/hr on a rough trail can be way more difficult to control than a spacecraft going 2 million.

the surface of that machine has to be strong enough to withstand the friction against the air particles, unles it is in space.

You can be pretty certain that any machine traveling more than 10,000 km/hr or so won’t be doing it near Earth. Although structural strength is not a major issue, air friction, which ultimately results in heating of the aircraft, is. The SR-71 Blackbird, widely considered the fastest aircraft ever flown, is capable of sustaining a speed of “only” about 3,600 km/hr, and that only at an altitude of about 24,000 m, where the air is much less dense than near the ground. Although made of very high temperature materials (titanium and composites), and designed to redistribute and shed as much heat as possible, the SR-71’s maximum sustained speed is due primarily to the limit of it to withstand a maximum skin temperature of about 430° C.

An experimental, unmanned X-43, which has very advanced skin cooling systems, reached a speed of 12,144 km/hr (about .00001 c) at an altitude of about 30,000 m during its 10 seconds of self-powered operation.

Making an aircraft capable of sustained speed much higher than the SR-71’s 3,600 km/hr would require a much more effective cooling system than any previously designed. This is a very fun engineering challenge to think about, and one that has a lot of valuable practical applications.

Even if the air friction problem and energy problems could be solved, the simple mechanics of keeping a vehicle close enough to Earth to be within its atmosphere at speeds approaching c appear prohibitive. The usual definition of “within the Earth’s atmosphere” is below an altitude of 100,000 m, or within about 6,478,137 m of its center. To maintain a circular path at this radius at a speed of .01 c (10792528 km/h) would require an acceleration of about 1387367 m/s/s (141568 gs), of which Earth’s gravity could supply only a bit fewer than 10 m/s/s (1 g). It’s hard to imagine any machine capable of exerting or withstanding the force of such an acceleration.

but some russian and german research intitutes are working on it.

Really? If you know of such research, please tell us about it, but given the tremendous engineering difficulties of making any vehicle capable of speeds even approaching .01 c, I’m doubtful any legitimate such research exists.

#329 The_Right_Stuff

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Posted 21 August 2007 - 02:54 PM

From what I understand, this magnitude of motion, known as the speed of light, is the only magnitude of motion of which all matter moves.

If an object is at rest in space, then this magnitude of motion is now directed across the dimension of Time only.

See
CONSTANT MOTION
to have a look at my point of view.

#330 Jay-qu

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Posted 22 August 2007 - 03:21 AM

From what I understand, this magnitude of motion, known as the speed of light, is the only magnitude of motion of which all matter moves.

If an object is at rest in space, then this magnitude of motion is now directed across the dimension of Time only.

See
CONSTANT MOTION
to have a look at my point of view.

This is not just your view but also Einstein's, is it not?

It appears that while something cannon move faster than light, it may be able to quantum tunnel faster than light

#331 The_Right_Stuff

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Posted 22 August 2007 - 04:56 PM

This is not just your view but also Einstein's, is it not?


Well so far I have been insulted, called a raving lunatic, and idiot, an delusional nut case etc. at Discussions - sci.physics.relativity | Google Groups , and they said that my theory was just a load of " utter crap " .

Another forum banned me from that forum because they said that my theory did not relate to the standard Special Relativity Theory, and thus they said I had no right to even speak of it.

And so I can not answer your question because honestly I think they are out to lunch.

#332 The_Right_Stuff

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Posted 23 August 2007 - 05:12 PM

Nothing at all is moving faster than light.

There are two kinds of events. One is a real time event, and the other is a Holistic event.

Space-Time exists. It is complete, it is real. Objects move within it.

When an event occurs it can be an event which was governed in real time, or from the across time holistic point of view.

Imagine that there were particles that had a spin property, and that these particles moved across space. The actual path that theses particles leave behind as they move across space, is a corkscrew like shape.

Now if these spinning particles were to interfere with each other in real time, then they will just interfere with each other as particles that were in specific places in Space at certain points in Time.

However, if these individual events were NOT monitored individually, then this would allow a huge Holistic event to occur instead. From the Holistic across time point of view, the entire corkscrew shaped path of the spinning particles would be seen all at once, thus in this kind of event a complete corkscrew shaped path interferes with another complete corkscrew shaped path. The end result gives the impression of a kind of wave behavior, rather than a particle like behavior.

Now since a holistic event could extend across any time period at all, then it can give the impression that information is being transmitted faster than the speed of light, when in actually fact particles involved within the holistic event were moving across space and so the holistic event not only extends across time, but across space as well.

#333 Jay-qu

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Posted 23 August 2007 - 06:14 PM

Have you read the elegant universe by brian greene? you seem to have some similar ideas - if not I suggest reading it, it may help clarify some ideas in your own mind :eek_big:

#334 The_Right_Stuff

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Posted 23 August 2007 - 06:34 PM

Have you read the elegant universe by brian greene? you seem to have some similar ideas - if not I suggest reading it, it may help clarify some ideas in your own mind :eek_big:


Actually, my ideas are complete.

#335 Jet2

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Posted 23 August 2007 - 11:03 PM

Yes.
Our thought.
Or make it more accurate, our imagination.

Jet2 :eek_big:

#336 alexander

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Posted 28 August 2007 - 10:27 AM

I have no idea of what you mean in your post jet2, but i am assuming you are replying to some earlier post maybe, just asking to quote if you are not posting about a post just above yours :D

Jay, I didn't mean to use a wormhole as an example, it is quite a bad one, i should know, teleportation would be more of what i am talking about. I think you got my point though, and it seems i was correct in my thinking which are both pluses :)

So here is more of my copylefted thoughts ;)
Alright, so, and i will still speculate on the experiment because its just so much fun :), if in theory and in QM they appear to, particles were to instantaneously change locations in space-time, and we redefine speed, we would also have to redefine all concepts that derive from speed, such as acceleration, force and such, i mean basically someone would have to sit down and rewrite all the physics. Because according to the current model (correct me if i'm wrong) particles that instantaneously change locations in space have not only infinite speed, but also infinite acceleration, with infinite forces acting on it, infinite force exerted and so forth. (and all those concepts are contradictory science) using Einstein's theories we can see that no object can possibly be instantaneously accelerated, and especially not to an infinite speed because it would require infinite energy to facilitate such a process, unless of course there is a massless particle, and one out of string theory and QM comes to mind, graviton. But then if there is a massless particle, you would have to redefine force, force is an action that accelerates a massive object, but what happens to a massless one, does that mean that a graviton can not be acted upon, but then how can the particle interact; if it cant then its not a particle, if it can then there is a force that it exerts and a force that effects it, and according to current definition of force, which derives from acceleration; force can not act on massless particles, so that leads to two conclusions: either one, gravitons are not massless and QM and strings are both false, or two there should be a new concept for instantaneous motion of particles or if we are to stick with current physics, instantaneous motion of massless particles... Another thought, gravitons in string theory are comprized of a number of strings which are a number of extra dimensions, and are said to be tied down to points in space-time, if the particles don't move then we do not have to redefine massless motion, but then what to do with instantaneous travel of massive particles, they don't have infinite speed, otherwise if in that instant the particle collides with another one moving even at the speed of light the universe would seize to exist because the force exerted by the collision would be infinite, no...?

I dunno where i am going with this yet, maybe i need to read on string theory a little more or QM or something. So much paradox in my view of the universe right now...
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#337 CraigD

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Posted 07 September 2007 - 07:29 AM

Posts from this thread contains discussion of Nimitz and Stahlhofen’s experiment, its details, underlying physics, and implications, have been moved to a new thread, FTL signaling via frustrated total internal reflection, because discussion specific to this experiment and effect was deemed a bit off the topic of this thread, which is more along the lines of the question of whether massive macroscopic stuff can travel faster than c.

#338 freeztar

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Posted 07 September 2007 - 08:40 AM

along the lines of the question of whether massive macroscopic stuff can travel faster than c.


I took the thread literally to mean "something", whether nanoscopic or macroscopic. Even a photon can be thought of as "something", right?

#339 Qfwfq

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Posted 07 September 2007 - 09:04 AM

Yes but I s'pose this thread was getting too long and clumsy for such a revived interest. :thumbs_up