Faster-than-light travel

Faster-than-light travel (often abbreviated to FTL) refers to the purported ability or potential to break the universal speed limit of light.

The poetry of reality
Science
We must know.
We will know.
A view from the
shoulders of giants.
v - t - e
This page contains too many unsourced statements and needs to be improved.

Faster-than-light travel could use some help. Please research the article's assertions. Whatever is credible should be sourced, and what is not should be removed.

How fast is it, Doc?

The maximum speed of light is exactly 299,792,458 meters per second (this is possible because the meter is actually defined by the speed of light), but is usually known as 3×108 meters per second. Although this is the speed of unstructured light in a vacuum and the speed of light is affected by the material through which it passes, the speed of light under any given circumstance is the maximum possible speed at that circumstance.

Some claim that this fundamental constant of the universe can be broken. But the amount of energy it takes to accelerate an object with rest mass rises sharply as c is approached until a discontinuity is reached. It would require infinite energy to cross the final gap.

Possibility of travel faster than the speed of light

Einstein's theory of general relativity does not rule out the existence of shortcuts in spacetime called wormholesFile:Wikipedia's W.svg which could permit the travel of a ship from one part of the galaxy to the other, bypassing the intervening interstellar space. An extraordinarily advanced civilization could conceivably construct artificial wormholes connecting a group of stars like a subway system. Carl Sagan described such a network in his novel Contact. However, even using wormholes to bypass the speed of light limit opens up possibilities of making "go back in time machines" (unless the science fiction author is very careful in restricting how wormholes can be made).

The Alcubierre driveFile:Wikipedia's W.svg is another hypothetical possibility. It requires the existence of negative mass. Even if negative masses exist, it would take as much energy as the sun produces over its entire lifetime just to create an Alcubierre warp field, let alone to make such a field move. However, a means of reducing the mass-energy requirements tremendously was theorized by physicist Harold White in 2012.

gollark: Is that a problem?
gollark: Hmm, at 10W of power utilization and 70 megaprayers per second, it's only 140 nanojoules per prayer.
gollark: But I doubt people use the entire processing capacity of their brain for prayers, given that a lot does vision processing and muscle control and whatever.
gollark: How much energy do people usually pray with? IIRC human brains run on something like 20W.
gollark: Yes.

See also
  • Light speed
This Physics-related article is a stub.
You can help RationalWiki by expanding it.
This article is issued from Rationalwiki. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.