Weighing the Internet

Brian Doherty | January 22, 2007

I'm not qualified to vouch for the math, but scientist and science journalist Russell Seitz calculates that "some 50 grams of electrons in motion make up the Internet." That doesn't include the chips or wires, though he goes on to think about those as well in the full post.

Comments

|1.22.07 @ 10:31AM|#

So that's just a bit over two souls weight, right?

|1.22.07 @ 10:36AM|#

They've done wonders developing ultra-light tubes.

thoreau|1.22.07 @ 10:51AM|#

Yeah, but what about the mass of all those photons? Huh?

|1.22.07 @ 10:54AM|#

It's considerably bouyed by all the hot air.

|1.22.07 @ 11:50AM|#

50...grams...of electrons.

OK, that officially blows my mind.

|1.22.07 @ 11:51AM|#

It's considerably bouyed by all the hot air.

Maybe, but also weighed down by all the bullshit.

|1.22.07 @ 12:02PM|#

50 grams of electrons should equate to about 50 X 1,860, i.e. about 100kg of photons. OK T, feel free to subject me to ridicule :-).

|1.22.07 @ 12:04PM|#

Now I wonder how much the electrons in the power networks weigh. Obvious, rather more...

Timothy|1.22.07 @ 12:15PM|#

WOW my mind is officially blown.

|1.22.07 @ 12:22PM|#

wayne,

Are you thinking about pRotons? Your calculation would be true for protons, but the mass of photons is hard to caclulate because they have zero rest mass. Their mass depends on how fast they are going.

|1.22.07 @ 12:26PM|#

I stand before you (or sit actually) a humbled man, thirty years distant from my chemistry and physics education. I am surprised that I remembered that protons were 1,860 time more massive than electrons.

Thanks Kent.

thoreau|1.22.07 @ 12:53PM|#

the mass of photons is hard to caclulate because they have zero rest mass. Their mass depends on how fast they are going.

They don't have any mass, and they all go at the speed of light. (We'll deal some other time with the details of what happens in materials with really high refractive indices, e.g. the "slow light" experiments that have gotten some attention in the press.)

I suggest that you all read the Feynman Lectures before you embarass yourselves any further!

:)

Pi Guy|1.22.07 @ 1:04PM|#

That's a big Twinkie.

|1.22.07 @ 1:21PM|#

Don't try to frighten us with your sorcerer's ways, Lord thoreau. Your sad devotion to that ancient science has not helped you to conjure up a shark with a laser on its head, or given you clairvoyance enough to find a quantum theory of gravity. . . .

For your insolence, I'm firing my deadly neutrino ray at you ;)

thoreau|1.22.07 @ 1:34PM|#

For your insolence, I'm firing my deadly neutrino ray at you ;)

Exotic weapons are no substitute for a good blaster on your hip.

Or a wookie to guard your back.

|1.22.07 @ 1:44PM|#

That's strange. My neutrino ray doesn't seem to work very well. My Chief Priest of "Science" says it's because neutrinos don't easily interact with matter. Fool! I've had his arms ripped off for his heresy.

Maybe my tachyon ray will work more effectively?

|1.22.07 @ 2:01PM|#

"and an Ampere is some ten to the eighteenth electrons a second "

If memory serves, an amp is 1 coulomb, 6.02X10^23 electrons per second. I think this might have a profound impact on this calculation.

thoreau|1.22.07 @ 2:34PM|#

An ampere is 1 Coulomb per second, but the charge of an electron is 1.6*10^-19 Coulomb, so about 6.25*10^18 electrons per Coulomb.

The 6.02*10^23 is the number of electrons (or anything else) in one mole.

|1.22.07 @ 2:38PM|#

Photons have momentum.
Momentum is defined as mass times velocity.
Photons have no mass.
Isn't even basic physics fun?

|1.22.07 @ 2:43PM|#

So that means I just need to shake up my 50g bag of electrons to get a second internet?

(Anyone care to calculate how deadly a 50g bag of electrons would be?)

|1.22.07 @ 2:48PM|#

Momentum is not defined as mass times velocity.

thoreau|1.22.07 @ 2:49PM|#

Once you get into relativity, momentum = mass*velocity is no longer quite true. Unless you use a velocity-dependent mass.

Two ways to do it:

1) For a particle with non-zero mass:

momentum = rest mass * velocity/sqrt(1-v^2/c^2)

where v is the velocity and c is the speed of light.

2) For any particle with energy E, momentum p, rest mass m (possibly zero):

E^2 = (m*c^2)^2 + (p*c)^2

where E = m*c^2/sqrt(1-v^2/c^2)

|1.22.07 @ 3:33PM|#

Alright, I thought the "Star Wars v. Star Trek" threads were the apogee of geekdom, but I see we are setting a new standard here.

|1.22.07 @ 4:14PM|#

R C Dean,

Upon blind faith,
They place reliance.
What we need more of
Is Science.

Thomas Paine\'s Goiter|1.22.07 @ 7:10PM|#

NERRRRRRRRRRRRRRRRRRRRRRRRRDS!

|1.22.07 @ 8:24PM|#

What about the Twinkie?

|1.23.07 @ 4:24AM|#

It's sad that a knowledge of physics is considered geeky or nerdy in the US. It's even sadder that "knowledge" of the personal lives of celebrities is not.

Could it be that the failures of democracy have something to do with this sad situation? That general ignorance of reality is the primary cause?