Can time be stopped ?

jasc15

PatPwnt said:
Time is stopped for photons. They don't experience time. If you could travel the speed of light, it would take you 0 time to travel any distance.
so if you travelled at c, like a photon, it would take you 0 time to travel any distance, which means that you would be everywhere in the universe at once! which makes sense due to length contraction. of course we are talking about limits where v->c, so it is asymptotic and you would never reach c.

Rudolf888

can time be stopped ?

This is a place it st....

King James Bible
And the sun stood still, and the moon stayed, until the people had avenged themselves upon their enemies. [Is] not this written in the book of Jasher? So the sun stood still in the midst of heaven, and hasted not to go down about a whole day

JDługosz

i think it would stop AT the speed of light ....

at a speed faster than light, it would go in reverse direction or something like that

anyway, yeah even I'm not sure in what context you're asking whether time can be stopped
Right, at the speed of light time stops.

Traveling faster than light, you could visit events that took place in the past. However, the "proper time" of the moving object becomes an imaginary number so I have no idea what that would do to physical processes experiencing it.

granpa

time stops at the event horizon.
it would also seem to stop behind an accelerating rocket (from the point of view of the rocket)
http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html [Broken]

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AJ_2010

Time is stopped for photons. They don't experience time. If you could travel the speed of light, it would take you 0 time to travel any distance.
So the photons that take 8mins to travel from the sun to earth experience no time?
Even though the time for us to measure them is taking 8mins?

In the 8mins that we observe, what is happening to the photon? Obvious answer is that it is traveling distance. But this raises the statement that to travel a distance you need a velocity and time. (Distance = Velocity/Time)

SinghRP

Yes, time stops -- virtually.

General Relativity: the time period of an atomic clock is dilated as the intensity of gravitational field increases. So, near a mass of infinitely high mass density, the time period would be infinitely large. That means the time virtually stops. However, nothing is really inifinte, so, time period could not be exactly infinity. (We blame many thing on infinity!)

However, if there is no mass anywhere, ... forget it. That means the clock is not there either. Moot point.

The same holds for an electromagnetic wave. The frequency is less near the mass than at inifilty. That is, wavelength expands, which is red shift. Near a mass of infinitely high density, wavelength of light tends to inifinity. That is, light virtually ceases to exist in waveform but still propagates at c.

Remember:
Frequency * Wavelength = c
Frequency * Time period = 1.

I hope this helps.

SinghRP

Light travelling faster than light! Imarinary relavistic mass. These are tachyons! I don't think they exist, but who am I to challenge you know whom.
Won't it wonderful if we can create tachyons and harness (use) them. We can see the past! And much more!

granpa

Yes, time stops -- virtually.

General Relativity: the time period of an atomic clock is dilated as the intensity of gravitational field increases. So, near a mass of infinitely high mass density, the time period would be infinitely large. That means the time virtually stops. However, nothing is really inifinte, so, time period could not be exactly infinity. (We blame many thing on infinity!)

However, if there is no mass anywhere, ... forget it. That means the clock is not there either. Moot point.

The same holds for an electromagnetic wave. The frequency is less near the mass than at inifilty. That is, wavelength expands, which is red shift. Near a mass of infinitely high density, wavelength of light tends to inifinity. That is, light virtually ceases to exist in waveform but still propagates at c.

Remember:
Frequency * Wavelength = c
Frequency * Time period = 1.

I hope this helps.
its a common misconception that infinite time dilation require infinite gravity.
time stops completely at the event horizon yet gravity is very finite at that point.

JaredJames

If anyone here is around the age of 20 and from the UK, they will know of a TV show called Bernards Watch. I think this is the type time stopping effect the OP is referring to.

For those of you not familiar, it is about a boy who has a pocket watch, when he clicks the top bit all time stops except for him (kids TV show, zero realism).

I only think this because of the way it was asked. From that viewpoint, it is strictly impossible.

rahuljayanthb

there are two ways time can be stopped.
1>at the speed of light: using einstein's formula, if v=c then denominator becomes 0.so naturally time stops.
this explains the immense stability of photons despite their high energy density.
2>at a region of high gravitational force such as within the event horizon of a black hole.

JDługosz

Light travelling faster than light! Imarinary relavistic mass. These are tachyons! I don't think they exist, but who am I to challenge you know whom.
Won't it wonderful if we can create tachyons and harness (use) them. We can see the past! And much more!
Even starting with the idea of a tachyon, it still won't let you communicate backwards in time! The laws conspire against it, even with that handicap! See http://math.ucr.edu/home/baez/physics/ParticleAndNuclear/tachyons.html" [Broken].

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QuantumPion

Gold Member
If you stopped time in your own reference frame, how would you know it?

Airman

Even if you could stop time how would you ever know? Nothing would happen. It would start again and you would never know it had stopped.

"Can time be stopped ?"

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