Andreas Hansen: PhysLink.com Expert

   Andreas Birkedal-Hansen
Andreas Birkedal-Hansen
M.A. Physics
Physics Grad Student
UC Berkeley 		Questions answered
to date:
11
Biography Andreas Birkedal-Hansen was born in Copenhagen, Denmark in 1972. He grew up in Denmark and Birmingham, Alabama. He received a B.A. in mechanical engineering and a B.S. in physics from Georgia Tech at the end of 1996. In 1999, he earned an M.A. in physics from UC Berkeley. He is currently at UC Berkeley working on a Ph.D. in physics.

His studies currently focus on theoretical particle physics, investigating implications for particle physics from recent and near-future cosmological data. His research efforts also touch on strengthening the connection between string theory and low-energy phenomenology through the use of effective supergravity models.

Click here for more information about his research interests. You can get more information about him by visiting: http://www.birkedal-hansen.com

Published Answers All answers by Andreas Birkedal-Hansen published at PhysLink.com up to date are listed here:
  1. Theoretically would light infinitely bounce, in a room made of perfect mirrors?

  2. What exactly is the heat death of the universe and where can I find out more?

  3. Why is it that when you put your finger over the tip of a hose the water shoots out farther?

  4. Why isn't the electron considered a black hole? It does have mass and its radius is infinitely small, isn't it?

  5. If two lasers 1 mile apart and facing each other emitted a pulse of light at the same time surely the relative velocity between these 2 pulses of light would be 2c (c=speed of light). I was under the impression that nothing could exceed the speed of light so what is the true relative velocity between the 2 pulses?

  6. When high velocity particles travel faster than the speed of light in a medium they create a blue flash. This is called Cerenkov Radiation, why does this happen and why is it blue?

  7. Why is it easier to accelerate an electron to a speed that is close to the speed of light, compared to accelerating a proton to the same speed?

  8. Now that the universe is proven flat, what implications does it have on the special theory of relativity, particularly the gravitational aspect?

  9. How was the critical density of the universe calculated?

  10. How are solar sails possible? If photons have no mass, how can they push on something?

  11. When annihilation occurs what happens with the charge of the interacting particles?