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| bio | website | ratsauce.co.uk |
|---|---|---|
| location | Chester, United Kingdom | |
| age | 52 | |
| visits | member for | 2 years, 5 months |
| seen | 10 hours ago | |
| stats | profile views | 3,291 |
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.
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13h |
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Is there any relation between weak and strong fields, similar to electric and magnetic fields? Ah yes, as in the quark gluon plasma. I bet there's still no (useful) classic long distance description though. |
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17h |
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How to calculate radius of the solvent? possible duplicate of How to estimate the physical size of a molecule? |
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1d |
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Mars just collided with Earth! A question of eccentricity @ChrisWhite: the existance of spring and neap tides suggests otherwise. |
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2d |
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Cosmology and TOE Yes. The laws we know about are approximations. |
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2d |
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can gravitational waves be detected experimentally arxiv.org/abs/1304.3473 |
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2d |
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Mars just collided with Earth! A question of eccentricity Orbits tend to become circular if there is significant tidal dissipation, and the tidal forces from the Sun on the Earth are significant. It's possible that the originally elliptical orbit relaxed to the current low eccentricity. NB you say "this value can change over time via long-range interactions with other planets" but it is the tidal forces from the Sun that matters, not the other planets, and these would act quite quickly on planetary timescales. |
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Jun 13 |
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Blackhole like properties of the Schwarzchild metric Related: physics.stackexchange.com/questions/28297/… |
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Jun 12 |
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Reflections in a glass of water I would guess it's total internal reflection at the glass-air boundary |
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Jun 12 |
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How would you swim in inviscid water? I would guess the Reynolds number for the flow around the arm is a lot higher than for the flow around the torso. I've never done the calculation, but it certainly feels that way when I swim. Someone is bound to have done the calculations. It would probably be worth some concentrated Googling if you want to pursue the question. |
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Jun 11 |
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Is it possible to take a picture of a star? @Gugg: to be honest I don't really know. Possibly it's simply because R Doradus is in the southern hemisphere and traditionally all the big stellar interferometers have historically (I don't know I this is still the case) been in the northern hemisphere. Betelgeuse is a lot brighter than R Doradus, but I don't know how big a difference this makes for imaging studies. |
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Jun 8 |
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Need some help, physics degree See also physics.stackexchange.com/q/2219 |
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Jun 8 |
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Need some help, physics degree possible duplicate of Book recommendations |
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Jun 8 |
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What exactly heats a pool of water on a sunny day A further quick Google found a spectrum of liquid water at backreaction.blogspot.co.uk/2009/01/… |
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Jun 8 |
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What exactly heats a pool of water on a sunny day To be honest I just took that figure from the Wikipedia page. A quick Google found commons.wikimedia.org/wiki/File:Solar_Spectrum.png and this does show a lot of the energy lies in wavelengths longer than 700nm. |
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Jun 6 |
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Non-associative operators in Physics Octonions crop up from time to time, and their multiplication is non-associative ... |
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Jun 6 |
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Question about negative mass @newera: can you provide a link to the article or book where Michio Kaku discusses negative mass. Kaku is a highly respected physicist, but he does lots of popular science TV shows that rely on a "Wow" factor to attract an audience. Consequently he often discusses topics that are not in the mainstream. There's no problem with this, we all do it, and if it gets people interested in Physics then I'm all for it. However I don't think it's always clear to the audience when kaku is discussing topics that are highly speculative. |
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Jun 6 |
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Does a scale measure weight or mass? I think Will's answer could be better written, but it is basically correct and the downvote is unfair. Will correctly says It measures the force your body exerts on the scale due to gravity. His final statement The scale then reads out this mass, m is correct for terrestial scales used on the Earth's surface. Maybe the limitations in his final statement could be explicitly stated. |
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Jun 5 |
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Why does the water diffuse at right angles in my coffee? Can you post a picture of the coffee? It's not clear from your illustration what you're observing. |
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Jun 5 |
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How exactly are the degrees of freedom seen by a falling into a black hole observer related to the ones seen by a staying outside observer? @Dilaton: the exterior Schwartzschild co-ordinates constitute a patch that does not cover the whole of the manifold. How this works technically is that once inside the event horizon you're outside the Schwarzschild patch. That's why there is no transformation between the two. In the Schwarzschild co-ordinates the inside of the black hole is technically covered by a separate patch that is disconnected from the exterior patch. However the interior patch is not physical so can't usefully be used to describe what happens. |
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Jun 5 |
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Is there any technique by which we can increse the speed of a car using the weight of the passenger in a car or bus? A stationary passenger can do no work because work requires a force to be exerted over a distance. Because no work is done no energy can be transferred to the car to accelerate it. You could fit the car with pedals and ask the passengers to pedal, or you could fire the passengers out of the rear window with a cannon. |
