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John Doty
  • Member for 2 years, 2 months
  • Last seen this week
30 votes

Time is the only dimension that has an arrow, and the only dimension which contributes an opposite sign to the metric. Is that just a coincidence?

23 votes

If I push someone, what fundamental force do I create?

22 votes

Why are there three bright spots in the first picture of Sagittarius A*?

17 votes
Accepted

Failure of Newton's corpuscular theory and success of photon theory of light

17 votes

Could the center of the galaxy explode as a result of a chain reaction of stars going supernova?

14 votes

On a magnetar, which force would exert a bigger pull on a 10 kg iron chunk?

13 votes

How is energy "stored in an electric field"?

12 votes

How does it make sense for the universe to have started from a big bang?

12 votes

Why do we even need RF cavities to accelerate particles?

10 votes

Can we get shock by ionic current?

9 votes

Is it possible to control frequency of the light?

9 votes

What is the connection between mechanics and electrodynamics that makes it necessary for both of these to obey the same principle of relativity?

8 votes

Has anyone charged an object with 1 coulomb? Why was such a ridiculously large charge chosen as the unit of charge?

8 votes

Why didn't the debris collapse back into the Earth at the time of Moon's formation?

8 votes

Why do X-ray telescopes have to be in space?

8 votes

How did they know the radius of the earth in ancient times?

7 votes

Does thorium-232 emit X-rays?

6 votes
Accepted

Uncertainty Principle in 3 dimensions

6 votes

When an electron hits a fluorescent screen mounted on a spring, why can't we get both position and momentum?

6 votes

What are some household sources of radiation detectable with a geiger counter?

5 votes

When I drink with a straw, is the atmospheric pressure pushing the water or me sucking it?

5 votes

How do headphones and earphones produce good bass if tiny speakers can't produce low frequency sounds very well?

5 votes

Why do microwaves penetrate flesh when visible light does not at the same intensity?

5 votes
Accepted

Why do photons: "have to give all their energy or none at all", in photon-electron excitation interactions?

5 votes
Accepted

A doubt about Kirchhoff's scalar diffraction theory

5 votes

Is photon path pre-defined at the time of emission?

5 votes

Is it "mathematically wrong" to ignore dual spaces, 1-forms, and covariant/contravariant indices in classical mechanics?

4 votes

How can the given formula yield a frequency, when it doesn't have a parameter with time units?

4 votes

Why Doesn't the Stefan-Bolzmann Law Deter Controlled Fusion Engineers From Seeking Extreme Temperatures To Maximize the $nτT$ Triple Product?

4 votes

Gravitational waves on rigid bodies

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