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Dec
19
comment Why isn't length contraction permanent even though time dilation is?
The length of space passed is in fact permanently contracted. Without loss of generality, consider a particle moving at C. For it the space passed contracted to 0 and the time passed was 0. If the space travelled were not permanently contracted, the particle would not be permanently at the new location after 0 time. Note that this does not imply that the distance can be traversed again in its contracted state.
Dec
14
awarded  Notable Question
Dec
13
comment Is a block of cotton heavier than a block of iron?
@Hypnosifl: Answer edited to address your comment. Thank you.
Dec
13
revised Is a block of cotton heavier than a block of iron?
Address comment
Dec
13
answered Is a block of cotton heavier than a block of iron?
Dec
2
comment Cooling a satellite
@HotLicks: EVA suits sublimate ice into vapor as a cooling method. I do believe that the vapor is recovered, though I'm not sure. A recent mishap with that system had water collecting inside a space suit, sending the astronaut rushing back to the ISS airlock.
Dec
1
comment Must Matter Particles Have A Hard Edge?
Thank you for this wonderful question, by the way. The answers generated are terrific and really cover the topic from all angles. Welcome to Physics.SE!
Dec
1
comment Must Matter Particles Have A Hard Edge?
It actually is smeared out, until it must interact (i.e. transmit a force)!
Nov
28
comment Why does rotation simulate gravity if motion is relative?
Arguably, this question and Draksis' link provide the background needed to understand exactly why we are still looking for a way to reconcile gravity with GR.
Nov
24
comment Why aren't there spherical galaxies?
@Ruslan: The OOrt cloud is such an example.
Nov
21
awarded  Popular Question
Nov
20
comment If your hair was on fire and you entered a vacuum, could you outlast the fire?
+1 for the information regarding the biological damage, which is missing in many of the other excellent answers.
Nov
5
awarded  Notable Question
Nov
5
awarded  Notable Question
Nov
3
awarded  Nice Question
Nov
3
awarded  Self-Learner
Nov
2
comment What are Stephen Hawking's main contributions to research-level physics?
You mention that you do not have the time to read 190 research papers. There is your answer. Hawking wrote or contributed to 190 research papers. That is quite the accomplishment.
Oct
14
comment How did Kelvin make this fascinating calculation?
This is such a beautiful answer, I wish that we could star answers as opposed to questions.
Oct
1
comment How empty of fuel are spacecraft booster rockets typically?
@David: Replace "half kilo" with "small but not infinitesimal" and "ipod" with "dirt, pollen, personal items, lice, urine still in the bladder, bird poop on the craft exterior, and other things that are not easily accounted for mass directly".
Sep
22
awarded  Popular Question