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4152276
bio website ratsauce.co.uk
location Chester, United Kingdom
age 53
visits member for 3 years, 8 months
seen 49 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.


1d
comment Potential that is proportional to distance
If $V \propto r$ the force is constant. In 1D this is trivial. Are you asking about the orbits you get in 2D?
1d
comment How do we know that space expanded with speed faster that a speed of light during big-bang inflation?
Spacetime was expanding during inflation, and indeed it still is, though it's expanding much more slowly these days. The requirement for homogeneity means the expansion is the same everywhere i.e. Hubble's law with the same value of the Hubble constant applies everywhere in the universe. Are you asking what expanding spacetime means?
1d
comment On boiling, does 1 kg of water give rise to 1 kg of steam?
Why do you think mass would not be conserved? If there is no mass entering or leaving your system then how can the total amount of matter change?
1d
comment How do we know that space expanded with speed faster that a speed of light during big-bang inflation?
There is no edge to the universe - this is actually addressed by several of the answers to the question you link. The Big Bang wasn't like an explosion that happened at a point, with the universe expanding outwards from that point. The theory used to describe the expanding universe (the FLRW metric) assumes that the universe is the same everywhere. This means it can't have an edge otherwise the points in spacetime near the edge would be different to the rest of the universe. The requirement for homogeneity means the universe is either infinite or it's closed - either way it has no edge.
1d
comment Undefined result of relativistic velocity addition formula
possible duplicate of Speed of light travel
1d
reviewed Approve suggested edit on What is a conservative force?
1d
reviewed No Action Needed Energy of moving capacitor
1d
comment Can you get a static shock in a vacuum if you are not touch the object?
@RayKay: Lemon means that if you consider a question to be satisfactorily answered you should click on the tick symbol to accept the answer you like best. This flags the question as answered.
1d
comment How fast until you feel wind in space?
possible duplicate of Would a fast inter-stellar spaceship benefit from an aerodynamic shape?
1d
comment Thermal healing of defects in crystals
Atoms do diffuse at room temperature, or at least they're mobile enough to allow dislocations to move. This leads to the phenomenon of creep.
1d
comment Has the universe we live in started as a black hole that is imploding?
@zibadawatimmy: to be honest I don't understand the maths well enough to comment. However note that energy is generally not conserved in an expanding universe because it violates time shift symmetry. There is no requirement for the new universe to have the same energy as the black hole it came from.
1d
reviewed No Action Needed How does velocity cause time dilation?
1d
comment Why does a brand new cricket ball swings?
This question appears to be off-topic because it shows insufficient prior research
1d
comment Why does a brand new cricket ball swings?
The obvious Google search finds lots of articles on this subject. In particular the top article gives an excellent description. To make your question more appropriate to this site it would be good to read through a few of the search results then come back to us with questions about specific issues related to physics.
1d
reviewed Reject suggested edit on The best way in which a man can pull a train
1d
answered Has the universe we live in started as a black hole that is imploding?
1d
answered Why is steel-reinforced concrete stronger than ordinary concrete?
1d
reviewed Delete Why is steel-reinforced concrete stronger than ordinary concrete?
1d
reviewed Leave Open Vertical Travelling - Taking Advantage of Earth's Rotation
1d
comment Vertical Travelling - Taking Advantage of Earth's Rotation
Why does this have three close votes for not mainstream physics? This is a simply question about dynamics so how can it possibly be not mainstream physics?