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Anarchy In Your Head

Something's growing in my pants. Uh huh huh. -Butthead

OK, seriously though. e = mc^2
Someone already said that but it really is a pitiful amount of mass. The speed of light is a really high number and then you SQUARE it! You get a crazy amount of energy from a tiny amount of matter which also means you get a tiny amount of matter from a hell of a lot of energy.

Tony H

Yes, photons have mass. They don't have RESTING mass. E=MC^2 and all that. Did Einstien die in vain?


This reminds me of the armchair theory I came up with. Only instead of everything expanding, everything is shrinking (at the speed of light). Now, this doesn't explain gravity, but it might lend some insight as to why the speed of light is constant, with the understanding that the shrinking behavior of light is different than matter.

Bryan P

Answer: No. Because photons radiate back out. Otherwise the earth would fry from all the heat.

Tomas Liubinas

IMO Answer: Yes photons have mass, but it (photon and mass) exists only when moving at speed of light. The moment they stop they stop existing or smth..

Greetings from Lithuania



Great blog, comic, books and etc!

To answer your question, photons leave Earth as often as they land on it. That's why you can see things. If all photons were absorbed when they reached Earth everything would be pitch-black. Perhaps a black hole?



I thought of something else.

People are writing - one pot of soil, one seed, yada, yada, yada

Weigh the water that you add to the pot.


(I'm going to join the herd I'm sure is above this post box)

PHOTONS HAVE NO MASS. only energy, which theoretically can be converted into mass, but that's not important to this discussion.


It's ok, we all make mistakes. Those new trees and people you see are not adding mass to our planet. They are converting raw materials and energy found on Earth to their new forms. If you want to get down to the nitty-gritty :) they are using the carbon and oxygen and nitrogen and iron and selenium to build their bodies, but these materials come from their foods (which is a bad arguement, because we only eat living things..AH HA! Where did THOSE things get their mass!?)

Well, eventually the food chain is brought back to plants and the plants get their mass from minerals in the ground around them, dead things in the ground around them, water, and the sun's energy. The energy from the sun does not increase the mass of Earth. (yes, I understand that E=mc squared, but that doesn't change my premise at all)

Photons have ZERO rest mass--just like quarks

And the mass from asteroids or dust or whatever DOES come to Earth...And gases (especially Hydrogen) escape our atmosphere...So we do lose and gain mass, but the amounts are so small and almost in equilibrium.
Ok, there's my rant, or explanation. You have a great day, and I personally liked Jesus (pronounced Hay-soos)


Scott, you once again display the grasp of science for which MBA's are justly famed. Photons have mass do they?
Are you sure? No-one else thinks so. Look at Wikipedia.

So that I can say something nice for once, 'Influence' was a really good book recommendation. Thanks for that.


I,m thinking the world's mass is increasing - probably because of the weight of all those extra servers required to hold you tube videos


I find strawmen devices especially delicious. I can poke a little fun at the giggly conspiracy nuts because any self- respecting industry-serving proletariat knows there are no conspiracies. When Dana Perino blurted out that she was not allowed to talk about the tanking dollar under threat of termination, that by no means implied that there was a conspiracy to suppress this information. Why not? Simple you tin foil hatted wonders: conspiracies don't exist! Everything is fine. Lets giggle some more and go max out another credit card!

......MS. PERINO: Wendell, I’m under strict instructions, and have been from the beginning, to not talk about the dollar, and I’m not going to get fired to satisfy your question.

Paul G

"Photons have mass? You fail high school science again? -) You're thinking about PROTONS?... surprised no one noticed.. I guess the whole hi IQ readership thing was a hoax."

Photons do have mass. They have no REST mass, but thats not the same thing.


Photons are massless, but they do have momentum. So when they strike the earth they transfer momentum to the planet, exerting an extremely weak force away from the sun, but don't increase the mass of the planet.


Photons do have mass, but unless they hit something that we see as black, they bounce off. That's why we can actually see things.

Dave Oblad

Ok, so I watched the video. Very interesting!
Cool morphing software!

This should be easy to prove one way or the other:

Continental connection or drift was first given weight,
not because of shapes fitting each other but by mineral
fingerprints. Cut a finger print in half. You can
match the ridges and mate the two half's again or deny
the two half's are the same print by the mismatching ridges.
So, edges of Pangaea were mapped by mineral fingerprints
to see how the continents were mated long ago.

Now.. If Pangaea was a single continent, then the outer
edges won't map to any other edges. If all the edges map
to opposing edges, then the video might hold water.

Speaking of water, I have no problem with water appearing.

Much of what hits the earth from space is just ice.
But that makes me wonder why mars is so dry.
Or, the water is simply being forced out of the earth
over time, like squeezing a wet sponge (sort of).

That the earth might have grown 100% from it's beginning?
Still, not a big deal, so lava cools and trapped water
forces it to expand like pumice. Still a cool notion.

None of which fits with the expanding universe.

Best wishes Scott! Just 2 more cents from Dave :^)


Someone said:

"You see, according to Einstein's relativity, now some of the most well-accepted and well-proven theories of the last century, there is a constant that NEVER changes. The speed of light in a vacuum. No matter what the effect of gravity are, light will always travel at the same rate in a vacuum"

Einstein showed, and it has been backed up by experiment, that light is, in fact, affected by gravity. Light does not always travel at the same rate in a vacuum, it's path is bent and it is slowed by very massive objects. Special relativity is only a special case of general relativity when gravity is set to zero.

Dave Oblad

Photons have Mass? Not when they are taking a break. (at

Actually, your right, the earth is bigger because of sunlight.
Sunlight converts to heat. Heat expands the distance between atoms.
Objects get bigger when hot. So the earth is slightly bigger because
of sunlight. However, on the side of the earth, away from the sun,
it must be dissipating that energy into space or we would go into
thermal runaway, oceans boiling, general hell on earth. So, we are
in thermal balance. So size remains somewhat constant.
Also, inversely, take away the sun and the atmosphere condenses to the
surface and the diameter of the earth is reduced. Atmosphere counts!

Of course, size is not a good indicator of mass. Which weighs more,
a ton of feathers or a ton of gold?

Anyway, as you somewhat understated, the earth is increasing in mass
by the hour, due to meteors and cosmic dust caught in our gravity well.
I am totally guessing, by I wouldn't be surprised if it amounted to
several tons per day. I know lots of it ends up under my bed.

I'd like to know if the lattice that supports matter is constant in size
or flexible? And if flexible, does gravity play a part?
See.. if the lattice were to expand, everything would expand, including
the space between everything. So, no local ruler would be able to measure
it because the ruler would be expanding too.

Here's a mind blower.. Distant galaxies are moving away from us at a
significant part of the speed of light. Now either we are still and that
galaxy is hauling butt.. or it's still and we are hauling butt.. or we
both are sharing the speed difference. In any case.. we are moving very
fast through the universe in some direction. Now, many know that matter
stretches in the direction of travel. So I might be twice as thick when
facing, say north or south, as when facing east or west.
So how come when I spin, I just look dizzy rather than looking like a
reflection in an undulating fun house mirror?

Maybe it's not enough to measure on my personal scale, but the earth is
huge and spinning. Seems like the shifting expansion and contractions
would be large enough to crack up the brittle surface and start them
moving all over the place. Oh wait! They are all cracked up and moving
all over he place.. never mind!

Fun Blog Scott. Best wishes to all from Dave :^)


photons happen to be massless...and trees and babies grow up by getting nutrition from outside, so their gain in mass is from the mass of all that they ate - so no net mass increase due to that either.


Umm photon's havent had mass since newton's corpuscular theory


"Photons have mass. What happens when all those photons from the sun hit Earth? Does the mass stay here?"

Assuming that no heat ever leaves the earth, then yes, the earth mass will increase by the amount of the photon mass. (heating -> energy -> E=mc2).
Gives a new meaning to global warming.


By absorbing photons, the earth gains energy and therefor mass. (This is fine, hot things weigh more than cold things, but the difference is trivial.)

As people are born, the matter that makes them up comes from the food that their mother eats, it doesn't `pop into existence'.

Overall the earth is actually probably loosing mass. Yes it gains some space dust etc, but at the same time, the top part of the atmosphere (ionosphere) is constantly leaking into interplanetary space (particularly when solar disturbances (coronal mass ejections) disrupt things). Again, this leak is trivial, so not significant over the course of human civilization, let alone a single life.

Chris Hulley

[Question: Photons have mass. What happens when all those photons from the sun hit Earth? Does the mass stay here?]

Yes, of course it does. Although strictly speaking, photons have energy, E = hc/l

where h = Planck's constant
c = speed of light
l (lambda) = wavelength

but the energy, when the photon is absorbed, contributes to the mass of the system that absorbs it. Strictly speaking, photons can also have a spin, which should be taken into account too.

Of course, the earth radiates a lot of energy, mostly as infra-red. This is electromagnetic radiation too, made up of photons, so there is a balancing effect. Nonetheless, the energy that is absorbed and retained in processes such as photosynthesis does add to the mass of the planet. Not much, because it takes a whole lot of energy to add up to a little mass. A nuclear explosion, big as it is, does not burn up all the uranium, plutonium, tritium etc involved, just a teeny bit of it.


actually photons don't have mass. But even if they did it wouldn't matter if the mass changed, since it's only energy that has to be conserved, not mass.

Bill B

Damn you, Scott Adams. Do you have any idea how much time this post inspired me to waste? What got me going was the idea that energy from the sun drives biological and a few chemical processes on the Earth. When this happens, the energy it takes to do whatever is done must add to the mass. I need to add here that we're probably talking a few parts per zillion (convenient name for a number I don't want to try to find). The time I wasted was in calculating how much mass the Earth could have gained from sunlight. I made a lot of totally unsupportable assumptions.
The Earth receives 1366 watts/square meter. I presents a disk-shaped outline to the sun with an area of 1.29X10^14 sq. meters. This has been happening for about 4.5 billion years. Assuming it is all absorbed (wildly inaccurate)and that the intensity hasn't changed (mildly inaccurate), I come up with 2.5X10^34 joules received from the sun. Plug that into E=MC^2 and you get 2.8X10^17 Kg. Even assuming that 99.9% of all solar energy is eventually lost to space, that still comes to 2.8 trillion tons! This, however is only about 5 trillionths of the mass of the Earth. Now I need to go get a life. Where did Hay-soos go after he was fired?

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