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  1. Blackberg

    And the 2021 Nobel prize for Physics goes to...

    Here's the Physics Today article: https://physicstoday.scitation.org/journal/pto Hopefully, people will soon leave their biaises and treat Earth physics the same way as other physics application, i.e. with objectivity. Many years ago, I had to leave this forum because of that problem (lack of...
  2. Blackberg

    And the 2021 Nobel prize for Physics goes to...

    Climate models! https://www.nobelprize.org/prizes/physics/2021/press-release/
  3. Blackberg

    How certain is dog domestication dating?

    I'm mostly trained as a physicist, so I'm wondering, on a scale from crackpot (1) to imressive (9), where does this hypothesis rank to an anthropologist? http://www.sciencedirect.com/science/article/pii/S1040618214002729?showall%3Dtrue%26via%3Dihub "I hypothesize that this innovation may have...
  4. Blackberg

    How is one second measured?

    Sundials. Hourglasses. Stargazing. Divisions by 24, and 60. You'd get there.
  5. Blackberg

    What is time?

    I was once mystified by time. Now I see it as nothing but counting something mechanical. Take a reference motion, such as the Earth rotation, and all of the "t"'s in physics equations could be replaced with "number of Earth rotations". Instead of "distance over time", speed could be defined as...
  6. Blackberg

    Other Micro- and Macroeconomics

    I'm interested in standard curriculum textbooks on micro- and macroeconomics. No holding back on math rigour please, I get annoyed by the law of demand presented as a straight line.
  7. Blackberg

    Present for finishing PhD

    A bottle of wine.
  8. Blackberg

    How do you think about math?

    All of math could be written in a spoken language. It's actually precision shorthand for surprisingly long sentences. Try reading Newton's Principia, you'll appreciate the current notation.
  9. Blackberg

    What are you currently reading?

    The Wikipedia in alphabetical order. Almost done with the "A" section.
  10. Blackberg

    How would you convert visible light to infrared or microwave

    Paint whatever black.
  11. Blackberg

    Chaos Theory and the Prolate Spheroid

    How does this compare to dropping a dice? Is there a distinction?
  12. Blackberg

    The old Newtonian gravity

    In physics, you use the simplest model that suits your purpose. Whichever error there may is included in the uncertainty.
  13. Blackberg

    When will the hot cup of tea cool faster?

    You could actually make two cups and do the experiement. Drop a thermometer in each, and clench only one. My hunch is that the clenched one cools faster.
  14. Blackberg

    Width of spectral lines

    Yes to temperature widening the spectral lines! Especially temperature I believe! Dark line because emission can happen in any direction other than towards your eyes!
  15. Blackberg

    Are eyebrows symmetrical?

    When I get a haircut, I bring a protractor and only pay if they get it symmetrical.
  16. Blackberg

    Graphene light bulb

    Not sure if referring to same device, but another lead here on similar topic: http://www.nature.com/nmat/journal/v14/n3/full/nmat4205.html. "We describe light-emitting diodes (LEDs) made by stacking metallic graphene, insulating hexagonal boron nitride and various semiconducting monolayers into...
  17. Blackberg

    Graphene light bulb

    According to http://www.bbc.com/news/science-environment-32100071 : "It is said to cut energy use by 10% and last longer owing to its conductivity." But of course whoever produces it certainly wants to sell it (which is not a bad thing).
  18. Blackberg

    Explain your avatar

    Coffee makes me happy.
  19. Blackberg

    Electron shape

    From the article : "the resulting momentum distribution will be smeared out and show interference fringes that depend on the different ionization times". "Four stroboscopic images taken at different XUV-IR delays (t0) are presented in Fig. 1(c) (a complete movie spanning one full optical cycle...
  20. Blackberg

    Why does a non-polar molecule imply insolubility in water?

    If you fill a bucket with rocks and magnets, what will happen? The magnets will clump together, and the rocks will be left to themselves. Same thing with polar and non-polar molecules (except with molecules, the electrical charge is prevalent over magnetic effects).
  21. Blackberg

    Is the universe truly expanding?

    If you're in space and you pull your hands apart, there doesn't have to be something coming in between. Space is just seperation between things. It's nothing but "distance" (Except if you want to talk about photons, cosmic particles, virtual particles etc.)
  22. Blackberg

    Newton's First Law of Motion

    Before Newton, people didn't know or realize that things could move on their own. He taught people that if something gets a push in one direction, it will need a push is the opposite direction to stop.
  23. Blackberg

    Thermoelectric devices and entropy

    If you heat one end of a wire, there is an initial current : the electrons run away to the other end as much as they can. But you very soon (seconds) get equilibrium because the first ones push back (- charged) the rest, which are left to bake in the heat (they actually don't mind that much)...
  24. Blackberg

    Fiber optic loop

    Absorption of light in glass is not zero, it depends on how many defects in the glass. The less defects in the fiber, the more light will keep its intensity. As for a single photon, the probability of absorption similarly depends on the purity of the glass. Fibers carry light accross oceans, and...
  25. Blackberg

    Correspondence between particle and string vibration mode

    Hi, my level of knowledge of string theory is the following : I understand that to each elementary particle there corresponds a string vibrating at an associated frequency (mode). So my questions are : 1. Is there some table yet that proposes a correspondence? Such as : electron : so many Hz...
  26. Blackberg

    Flexible cylinder

    With flexibility, you're ruing out ceramics. With 1000 C, I think you're ruling out anything that's carbone-based (plastics etc). You're left with metals. With my current knowledge, I doubt such fine details can be had on a such a scale (0.01 mm X 100 mm tunnel within a metal?). I'll be curious...
  27. Blackberg

    How to divide a cylinder

    The lines you have in post 7 are strange. I do not see where the holes are.
  28. Blackberg

    Flexible cylinder

    How much do you need it to flex? Does flexibility need to be elastic (return to original shape when not stressed)? How many 0.01mm holes do you need? At what temperature will this be operating?
  29. Blackberg

    Does anyone here have a patent?

    Either yourself, or with partners, or through your employment? If so, would you care to share how it came along and what's it about?
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