# Object faster or just as fast as light

## Recommended Posts

What if someone designed a space ship that travelled faster than light? And they managed to prevent the space ship from crushing into another object and from disintegration (because of the speed)

##### Share on other sites

9 minutes ago, Irma said:

What if someone designed a space ship that travelled faster than light? And they managed to prevent the space ship from crushing into another object and from disintegration (because of the speed)

Nothing with mass can travel at or exceed c.

Reaching a speed 'near' c, will shrink how long a journey is down to next to nothing though(assuming you and your ship can survive).

##### Share on other sites

• 1 month later...

Although you can't change the speed of light, you can change the wavelength if the light is first absorbed by a substance's electrons then put them into an excited energy state. When the electrons return to their normal ground state they will emit light of the particular wavelength corresponding to hte energy difference between the two states.

##### Share on other sites

57 minutes ago, PyriteFalcon0829 said:

Although you can't change the speed of light, you can change the wavelength if the light is first absorbed by a substance's electrons then put them into an excited energy state. When the electrons return to their normal ground state they will emit light of the particular wavelength corresponding to hte energy difference between the two states.

Your answer seems (a) irrelevant to the question asked and (b) does not seem to explain how the process you describe changes the wavelength, given that the light absorbed is the same wavelength as the light emitted unless certain other processes are also involved.

##### Share on other sites

• 3 months later...
On 8/28/2023 at 2:32 PM, Endy0816 said:

Nothing with mass can travel at or exceed c.

Not by conventional means but there are theoretical ways of breaking the lightspeed barrier, such as if you were somehow able to move space itself and "ride" it, much like a surfer riding a wave.

##### Share on other sites

32 minutes ago, Photon Guy said:

Not by conventional means but there are theoretical ways of breaking the lightspeed barrier, such as if you were somehow able to move space itself and "ride" it, much like a surfer riding a wave.

But there is no theoretical way to move space itself.  It's a bit like saying we could all fly if we could switch gravity off. Which is sort of true, except that we can't switch gravity off.

##### Share on other sites

44 minutes ago, exchemist said:

But there is no theoretical way to move space itself.

I think they're referring to the Alcubierre metric, which doesn't actually move space but rather creates a configurable energy density field that can "push" something massive, assuming you can create a negative energy density somehow.

##### Share on other sites

39 minutes ago, Phi for All said:

I think they're referring to the Alcubierre metric, which doesn't actually move space but rather creates a configurable energy density field that can "push" something massive, assuming you can create a negative energy density somehow.

Yeah....assuming you can create -ve energy density somehow........

Which is a bit like switching off gravity, if I'm not mistaken. 😀

##### Share on other sites

3 hours ago, exchemist said:

But there is no theoretical way to move space itself.  It's a bit like saying we could all fly if we could switch gravity off. Which is sort of true, except that we can't switch gravity off.

Space itself apparently could be moved by using objects with negative mass. The problem is finding matter that has negative mass which so far only exists in theory but it is a possibility.

##### Share on other sites

Energy and mass are equivalent properties.
You cannot have negative mass without negative energy, and the same arguments against their existence apply to both.
Only 'exatic' matter is postulated to have negative mass/energy, but it could be just an 'accounting' trick as it is the complement of Hawking Radiation and must be harvested just inside the event horizon of a Black Hole.
Good luck with that.

The speed a light, c , is reserved for massless particles and nothing having any mass can reach that speed.
At one time Tachyons were postulated, which move faster than light and cannot ever slow down to the speed of light, travelling backwards in time.
The term Tachyonic has recently gained a new meaning.
Particles or quantum fields with imaginary/complex mass are unstable, and said to be tachyonic.

see here          Tachyon - Wikipedia

and here         Tachyonic field - Wikipedia

##### Share on other sites

6 hours ago, Photon Guy said:

Not by conventional means but there are theoretical ways of breaking the lightspeed barrier, such as if you were somehow able to move space itself and "ride" it, much like a surfer riding a wave.

Any ones that don't require new physics?

##### Share on other sites

1 hour ago, swansont said:

Any ones that don't require new physics?

None that I can think of, but the point is that just because the lightspeed barrier can't be broken by conventional means doesn't mean it can't be broken period.

##### Share on other sites

33 minutes ago, Photon Guy said:

None that I can think of, but the point is that just because the lightspeed barrier can't be broken by conventional means doesn't mean it can't be broken period.

If new physics is required, how do you then answer the question in post #1 ?

##### Share on other sites

1 hour ago, Photon Guy said:

None that I can think of, but the point is that just because the lightspeed barrier can't be broken by conventional means doesn't mean it can't be broken period.

All science is provisional. But until there’s an experimentally-verified model, this is just appealing to magic.

##### Share on other sites

Sometimes the models we build allow for predictions which are non-physical.
They are 'weeded out' by inconsistencies that arise ( you should look into some of the absurd properties negative mass would have ), or experimental observations.

##### Share on other sites

On 1/29/2024 at 9:23 AM, Photon Guy said:

Not by conventional means but there are theoretical ways of breaking the lightspeed barrier, such as if you were somehow able to move space itself and "ride" it, much like a surfer riding a wave.

c is more the point at which you run out of road in terms of distance and time.

Might be possible to bypass with something like a wormhole, but you likely can't reach/push through it due to the inherent paradox.

##### Share on other sites

18 hours ago, Photon Guy said:

None that I can think of, but the point is that just because the lightspeed barrier can't be broken by conventional means doesn't mean it can't be broken period.

As pzkpfw alluded to, If it requires a new, now unknown, physics to allow for FTL,  then it is pointless to speculate about what would happen, because we have no idea what rules we'd have to adhere to in this new physics.

## Create an account

Register a new account