233 reputation
16
bio website
location
age
visits member for 4 years, 5 months
seen yesterday

Jul
16
comment Could quantum computers break any cipher?
The fundamental issue is that quantum computers don't let you compute all possible inputs in parallel: quantum computing isn't nondetermanism.
Jul
16
comment Could quantum computers break any cipher?
This isn't how quantum computers work. The belief that they can is so common that Dr. Aaronson has an entire section of his blog devoted to this misconception: Speaking Truth to Parallelism. They do give speedups for some problems, but not nearly as many as that would suggest. (Basically, we don't think that BQP = PSPACE.)
Apr
2
comment Could any object have zero mass?
@mattecapu: When it's not singular, sure.
Feb
17
comment What Planck units are limits?
@JimdalftheGrey: I tried to handwave away the small constant factors with "approximately". But I'm just looking for a general explanation here, within current understanding.
Feb
17
asked What Planck units are limits?
Jan
29
comment Physical Constraints of Very Large Humanoids
100 tons scales to 60 pounds (optimistically assuming 2m height) which seems very light for an average adult male. 250-350 tons is more reasonable depending on what you assume for height.
Jan
29
comment Physical Constraints of Very Large Humanoids
For comparison, its weight would be between one and two blue whales. So it's not an implausibly large creature, just ill-suited to land-dwelling bipedalism.
Nov
13
comment How large can an atom get? What's the farthest an electron can be from its nucleus?
See also my closely related question physics.stackexchange.com/q/144819/2818
Nov
6
comment What is the most efficient information storage?
@WetSavannaAnimalakaRodVance: I don't think it scales as $n$ but rather as $n^2$ (making the volume scale as $n^6$), see physics.stackexchange.com/q/144819/2818
Nov
5
comment What is the most efficient information storage?
@WetSavannaAnimalakaRodVance: Doesn't the radius scale as $n^2$? But in any case having $n^3$ distinguishable states isn't a problem, since they only contain $\log_2(n^3)\sim k\log n$ bits of information.
Nov
4
comment How big is an excited hydrogen atom?
:) No need, just curious.
Nov
4
comment How big is an excited hydrogen atom?
In other words, for large enough $n$, it would be difficult to measure $n$ accurately.
Nov
4
comment How big is an excited hydrogen atom?
Thank you! Does the "some more" mean multiplying by a (large) constant, or will it scale up faster as $n$ increases?
Nov
4
accepted How big is an excited hydrogen atom?
Nov
4
asked How big is an excited hydrogen atom?
Aug
14
comment When a star becomes a black hole, does its gravitational field strength become stronger?
This applies once the ejecta pass the planet's orbit, right?
Aug
3
awarded  Commentator
Aug
3
comment Forces other than the fundamental interactions, e.g. friction
Nice answer. Any suggestions on where I could learn more (at a fairly basic level) about the $r^{-6}$ interaction? (E.g., why is the next term not $r^{-4}$?)
Jul
2
awarded  Curious
Jun
27
comment Are galaxies “disk” shaped?
We often see them edge-on, so we have a pretty good idea of what general galaxies' z-axes look like.