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2021-12-10: 2021 End of Year AMA!

  • 00:02: ... there a required a type of energy that doesn't exist and that is uh a negative energy density so as far as we know energy can only be positive um in you know ...

2021-04-21: The NEW Warp Drive Possibilities

  • 04:48: We can summarize this by saying that it requires a negative energy density, which should be impossible except perhaps on the tiniest, quantum scales.

2020-04-22: Will Wormholes Allow Fast Interstellar Travel?

  • 08:42: ... common way to think of exotic matter is anything with negative energy density. Something with negative mass could produce the required negative ...
  • 09:44: ... existing in that region. The gap between the plates will then have a negative energy density relative to surroundings. Unfortunately, the Casimir effect is very, ...
  • 10:15: ... the wormhole would have to pass through this region of extremely high negative energy density, which probably wouldn’t be healthy. Matt Visser, who literally wrote the ...

2019-10-21: Is Time Travel Impossible?

  • 05:37: Really what we need to open the wormhole is a negative energy density.

2019-01-09: Are Dark Matter And Dark Energy The Same?

  • 08:02: Well a constant NEGATIVE energy density – like the one proposed by Farnes, gives a negative cosmological constant.
  • 10:16: Does a universe with a constant negative energy density fit the observations?
  • 11:00: ... an age for his universe of 13.8 billion years assuming a very low negative energy density, but that really just corresponds to the very first straight part in the ...

2015-10-28: Is The Alcubierre Warp Drive Possible?

  • 03:24: ... do this for the warp field, you find that you need to produce a ring of negative energy density in a band around the ship to produce the right warp ...
  • 06:18: Now, this would be a field created by positive, not negative, energy density.
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