108,768 reputation
4165295
bio website ratsauce.co.uk
location Chester, United Kingdom
age 53
visits member for 3 years, 9 months
seen 8 mins 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.


Oct
16
comment Is there a null incomplete spacetime which is spacelike and timelike complete?
This paper claims to describe just such a spacetime, however it's behind a paywall.
Oct
16
comment What prevents a star from collapsing after stellar death?
Have you Googled for relevant articles? For example this one on Wikipedia? After reading such articles what precisely are you unclear about?
Oct
16
comment What holds an atom together?
(1) is a duplicate of The Nucleus of an Atom. (2) is a duplicate of several questions. For (3) see the strong interaction. For (4) see preons. For how to ask a question see What counts as sufficient prior research when asking a question?.
Oct
16
comment What holds an atom together?
possible duplicate of The Nucleus of an Atom
Oct
16
comment What is the difference between wigglers, bending magnets and undulators?
This question appears to be off-topic because it shows insufficient prior research
Oct
16
comment Why do the big nuts always remain at top? The Brazil-nut Effect
@TreyTaylor: granular flow is a surprisingly hard problem. There are many aspects of it for which we don't have a good quantitative description.
Oct
16
comment What are the differences between the conventional mosfets and tunneling mosfets
This question appears to be off-topic because it is shows insufficient prior research
Oct
16
comment Is the temperature rise caused by reflection of sunlight linear?
Related: Heat production of magnifying glass. The same argument applies to mirrors if you replace the area of the lens by the cross-sectional area of the mirror.
Oct
16
comment What is DX technology and what are the effects on digital cameras?
Hi Katarina. My comment was meant for other site members who may never have seen an aluminium smelter. I can't think of any reason why the cell should have affected a film camera. I'd guess it generates a magnetic field field, but I'm surprised that the field is strong enough to affect a camera.
Oct
16
comment What is DX technology and what are the effects on digital cameras?
Note that DX Technology is a brand name for an electrolysis cell made by DUBAL.
Oct
16
comment Building a wormhole
Thanks, but there are lots of articles on analysing the spacetime around existing wormholes. My question is what would happen when you started in flat spacetime and assembled the material to construct a wormhole. To create the usual Morris–Thorne wormhole would appear to require a topology change, and this is what I find odd.
Oct
15
comment Time and space slow down and converge in a black hole
The Big Bang and the singularity at the centre of a black hole are completely different and described by different mathematics. The Big Bang is described by the FLRW metric and a (stationary) black hole is described by the Schwarzschild metric.
Oct
15
comment Why does the sun have its magnetic field
This question appears to be off-topic because it shows insufficient prior research. The most basic of Google searches finds many articles on this subject, such as this one.
Oct
15
comment Are there any radiation emitted from the cameras?
All electrical equipment radiates some electromagnetic waves. Can you be a bit more precise about what you think a video camera might be radiating and why?
Oct
15
comment How comes, that for Gravitational Waves H-atom size we need energy of a neutron star, but for the warp-drive only negative mass of jupiter?
Both neutron stars and the Alcubierre drive produce a static spacetime curvature. However gravitational waves require an oscillating curvature, and this is much harder to achieve. Two neutron stars in a close orbit will radiate substantial amounts of gravitational waves, but an Alcubierre drive won't produce any gravitational waves.
Oct
15
comment Normalization of a wavefunction that's superposition of two unknown energy eigenfunctions
CuriousOne's point is that $<u_i|u_j> = 0$ and $<u_i|u_i> = 1$, so your integral is simply $25A^2$.
Oct
15
comment How can we assume that reaching the speed of light slows down time?
Though the question is phrased in an unclear way I'm guessing it's asking about the physical reality of time dilation. In that case there are several questions that address this issue.
Oct
15
comment Accelerating Tetrahedron
The question (which is facing imminent closure anyway) is presumably meaning that the top ball is accelerating downwards and displacing the other four balls sideways.
Oct
15
comment What does the “size of the universe” mean if the Universe is infinite?
This question appears to be off-topic because it is asking about the meaning of a commonly misused phrase.
Oct
15
comment What does the “size of the universe” mean if the Universe is infinite?
The phrase size of the universe is used in two ways: (1) to mean the size of the currently observable universe, or (2) to indicate that the speaker has no understanding of general relativity.