109,111 reputation
4166295
bio website ratsauce.co.uk
location Chester, United Kingdom
age 53
visits member for 3 years, 9 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.


May
5
comment What exactly is an anti-neutrino?
@Yashbhatt: see Identification of particles and anti-particles. It is possible that neitrionos are Majorana particles though I get the impression this idea is going out of fashion.
May
5
comment Is there any significance of atomic orbitals?
See journals.aps.org/prl/abstract/10.1103/PhysRevLett.110.213001, we have actually measued the atomic orbitals of hydrogen. See also Anna's answer to Is there anyway to use a scientific instrument to measure the density of electron around the atomic orbital?.
May
5
comment How close does light have to be, to orbit a perfect sphere the size and mass of Earth?
Yes, there are a few issues with that first paragraph, so I've rewritten it. @think123: no, you can't get light to orbit the Earth.
May
5
comment Effect of wavelength on photon detection
This question is related and might be of interest. The question deals with photon emission, but that is just the time reverse of absorption.
May
5
comment How did WMAP measure the flatness of space?
See planck.caltech.edu/pub/2013results/Planck_2013_results_16.pdf. Both $\Omega$ and $H_0$ are obtained from fitting the CMB data. You do not require one to be known to calculate the other.
May
5
comment How do traveling waves pass through a standing wave node, if the node doesn't move?
Hmm, I'm not sure that's really a duplicate ...
May
4
comment In which direction does the current flow in a wire moving north to south along the Earth?
Hmm, I see your point. Assuming the wire is oriented east-west then if it's moving from north to south it isn't crossing any field lines. Having said this, the field is only parallel to the Earth's surface at the equator. In the northern hemisphere the field lines point slightly upwards out of the Earth and in the southern hemisphere the field lines point slightly downwards into the Earth (or is it the other way round - I can never remember which way magnetic field lines point).
May
4
comment How did WMAP measure the flatness of space?
Also see What are the different ways to measure the spatial curvature of the universe?. Actually this has a better discussion that the duplicate I've suggested but I can't change the close vote now.
May
4
comment Is light and sound waves interconvertible?
This question can be answered by reading a Wikipedia article
May
4
comment Magdeburg Hemispheres
@TylerP: remember that the force is a vector. When DumpsterDoofus integrates the force over the hemisphere the components normal to the rope between the horses will cancel out (due to the axial symmetry) and you are left with just the components parallel to the rope. That's why integrating over the hemisphere is correct and gives the correct value for the force required to pull the hemispheres apart.
May
4
comment Gravity fed containers
Can you draw a diagram to show what you're asking about?
May
4
comment How do we know quantum entanglement exists/happens?
have you read the Wikipedia article on entanglement? That cites numerous experimental tests of entanglement.
May
3
comment hawking radiation
It may not be obvious that the question I've linked is a duplicate, but the answers to it answer your question as well. In brief, you are confusing negative energy particle with antiparticle.
May
3
comment Why does Pyrex glow orange under UV?
The phenomenon is called fluorescence. I didn't think Pyrex (aka borosilicate glass) had any significant fluorescence, so I don't know why your empty beaker was producing orange light.
May
3
comment Why do grey body radiators not heat up?
I think we need a link to the document where you saw this statement so we can see the context. Also whoever made it can't add :-)
May
2
comment Stepping into a pool of water - shock - why?
Related, and possibly a duplicate, Would Beetee's electrocution plan work and kill the tributes in the lake?
May
2
comment Nuclear waste reclamation
Indeed, an old school friend of mine used to work for the company that reprocesses fuel in the UK.
May
2
comment Kinematics and Motion
@user45332: your question was answered, in some detail, in the question Number of planks required to stop the bullet
May
2
comment Find the exact angle as a function of time for a rod that swings on a frictionless axle
Your system is a rigid rod pendulum, and it's an anharmonic oscillator. In general there is no closed form solution for anharmonic oscillators, and there isn't in this case.
May
1
comment are sub-atomic particles really particles or mere concepts in our minds?
This question appears to be off-topic because it is about philosophy not physics