113,972 reputation
5176303
bio website ratsauce.co.uk
location Chester, United Kingdom
age 53
visits member for 3 years, 10 months
seen 5 hours ago

Semi retired old time computer nerd who started programming on a Commodore Pet.

Since I'm also active in the Physics forum I should add that I started as a theoretical chemist, moved into solid state photochemistry and finally worked in industry as a colloid scientist. I only became a full time computer nerd in 1997.


17h
reviewed Close 3D harmonic oscillator problem
17h
answered Best way to heat something in aluminum foil?
17h
comment How does virtual particle become real particle in Hawking radiation?
The virtual particle explanation is only an analogy and not to be taken seriously. See the linked question for what actually causes Hawking radiation.
1d
comment How did the Huygens probe use EM waves to measure wind speeds on Titan?
@karthikeyan: the experiment measured the lateral speed of the Huygens probe. Because the probe is dangling from a parachute being swept along by the wind it's assumed that the lateral speed of the Huygen's probe is roughtly the same as the wind speed. So this gives us an indirect measurement of wind speed.
1d
reviewed Approve suggested edit on If angular momentum is conserved, what's wrong with this scenario?
1d
comment Show that there exists a Lorentz transformation such that two events are happening at the same time?
Consider what happens to the $x'$ axis as you increase the boost.
1d
reviewed Close how do you safe-keep cube beam splitter?
1d
reviewed Leave Open How to calculate gauge pressure at water depth?
1d
reviewed Close Did the derivation of self inductance equation overcalculate winding number?
1d
reviewed Close How many physical constants should there be?
1d
comment Why are dishwasher washed glasses “squeaky clean”?
@PiotrDobrogost: sodium hydroxide reacts with silica to produce sodium silicate, so sodium hydroxide will dissolve silica but only exceedingly slowly. However this is chemistry not physics.
1d
comment Is uncertainty in velocity via HUP reference frame dependent?
Agreed. First year students tend to be taught an over-simplified and potentially misleading version of the uncertainty principle, presumably to stop their brains melting. If it's OK I'll flag this as a duplicate of the question I linked above.
1d
answered Electron-positron annihilation to neutrinos
1d
comment Is uncertainty in velocity via HUP reference frame dependent?
Yes, I am saying the uncertainty does not arise from your measurement technique. See Is uncertainty principle a technical difficulty in measurement? for more on this.
1d
reviewed Delete If angular momentum is conserved, what's wrong with this scenario?
1d
reviewed Reject and Edit suggested edit on Why does the Sun always rise in the East?
1d
revised Why does the Sun always rise in the East?
Typo
1d
reviewed No Action Needed how do you safe-keep cube beam splitter?
1d
reviewed No Action Needed Andreev reflection graphene - metallic superconductor
1d
comment Is uncertainty in velocity via HUP reference frame dependent?
If I measure a velocity as $v \pm \Delta v$, then the uncertainty is $\Delta v$ and whether $v$ is large or zero makes no difference. From purely practical considerations it's probably easier to measure a velocity accurately if it's small, but the error due to the uncertainty principle is not due to practical considerations.