Comments on: The Dark Energy Song

By: e zahniser

e zahniser — Sun, 25 Oct 2009 14:59:03 +0000

great! you need the lyrics while listening
they are available if you just google knox,lloyd
and click on dark energy lyrics

By: Ry Sal

Ry Sal — Sun, 18 Oct 2009 16:03:23 +0000

I might have paid attention to this guy.

By: The Dark Matter Song | Hey Zeitgeist

The Dark Matter Song | Hey Zeitgeist — Sat, 17 Oct 2009 19:28:48 +0000

[...] tip: Discover [...]

By: Alison

Alison — Tue, 13 Oct 2009 05:41:14 +0000

I like the song, though the mention of a “He” is somewhat puzzling, if the song is trying to teach students about a scientific concept. In any case, Professor Knox is a talented musician. I wish one of my professors would do something like this… I seem to only catch such moments on YouTube! (I am a UCD student, who loves Cosmic Variance.)

By: polymath

polymath — Mon, 12 Oct 2009 23:36:59 +0000

To David Degner: This analogy is well-known, but what you have only works for *classical* gravitation. If you do relativistic gravitation, there is even more that can be done. In particular, there is an analog to the magnetic field (with a VxB term in the ‘Lorenz force law’). The main difference is that ‘mass’ has only one sign, instead of the ‘charge’ which can be either sign (positive or negative). This comes about because gravity is a tensor interaction (spin 2) rather than a vector interaction (spin 1).

By: Brian

Brian — Mon, 12 Oct 2009 05:09:03 +0000

Please adopt a strict one post per day policy on this blog. Seriously, there are like seven of you. Give each person a day of the week if you have to. Tired of coming here and being disappointed.

By: Tim

Tim — Sat, 10 Oct 2009 23:40:15 +0000

The fact that it’s set to the tune of one of my all-time favorite songs certainly clenches this one for me. Hooray!

By: daniel

daniel — Sat, 10 Oct 2009 21:48:28 +0000

Lloyd rocks!

By: Sean

Sean — Sat, 10 Oct 2009 18:54:15 +0000

Here are the lyrics to the dark energy song.

By: Spacetiger

Spacetiger — Sat, 10 Oct 2009 13:07:31 +0000

ok, can’t make out the lyrics completely.. any chance of subtitles?

infinitely cool nonetheless!

By: onymous

onymous — Sat, 10 Oct 2009 12:43:04 +0000

This is great. I like how one bit of the original lyrics (“… have found in this place that is circling all ’round the sun…”) shows up toward the end.

By: Brian Too

Brian Too — Fri, 09 Oct 2009 23:36:25 +0000

Remarkable!

By: casey rentz

casey rentz — Fri, 09 Oct 2009 22:00:35 +0000

Is this set to the tune of one of Jeff Mangum’s songs…I believe it is! Which song?’In The Aeroplane Over The Sea’? Fantastic. Great adaptation! I love science set to music.

the original song: http://www.youtube.com/watch?v=q2jkyuT8unw

By: Sili

Sili — Fri, 09 Oct 2009 21:25:29 +0000

Sorry, can’t make sense of what he’s saying.

So, is this also why you’re too busy posing for the SkepDude calendar to make money for Donors Choose?

By: Matt

Matt — Fri, 09 Oct 2009 20:16:54 +0000

OK, any song at all based on a neutral milk hotel track is genius is my book. Could be about the damn flat earth and it would still rule. Neutral Milk Hotel + cosmology = greatest thing ever.

By: David Degner

David Degner — Fri, 09 Oct 2009 19:17:25 +0000

Sean, off topic but since you are an expert on gravity I am really curious if you also observed the following parallel? Maybe you could do a future blog on it.

There is an interesting parallel between the electric field and the gravity field, a duality if you will. It leads to a 5th Maxwell equation.

In the electric field we have Coulomb’s Law F = q1q2/4πεR^2. The analogous entity in gravity is Newton’s Law of Gravitation F = Gm1m2/R^2. In the electric field the energy stored in the electric field of a spherical single plate capacitor with radius R and charge q is given by U = q^2/8πεR. The gravity analogue for the energy stored in the gravity field by a spherical mass m is U = Gm^2/2R.

The analogue of the electric field vector in gravity is a gravity field vector that I have named Newton Height or NH for short:

NH = Gm/R^2 (direction unit vector R)

The gravity analogue to Gauss’s Law for the Electric Field, Maxwell’s fifth equation, the Law for the Gravity Field:

∫ NH • dA (closed surface) = 4πGm

For the electric field we figured out the field strength and direction using Gauss’ Law and integrated the electric field energy density μ = ½ εE^2 over all of space from the surface of the charge to infinity in all directions to get the energy stored in the field. The energy density of a gravitational field is given by μ = (1/8πG) NH^2.

Then for Newton’s law of gravity we have F = mNH analogous to F = qE and F = − del U(gravity field) analogous to F = − del U(electric field).