I would like to know other "bad science" foruns.

Now I'm debating with a guy that says atoms doesn't exist and I think this wouldn't be astronomy.

Anyway, do you know a simple way to prove their existence?

Jairo.

Use google. Search Images with the phrase "scanning tunneling microscope" or "atomic force microscope". (These microscopes can be used to view and manipulate individual atoms.)

Also, ask him how fluids can mix if they are continuous instead of having discreet components!

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If ignorance is bliss, why is the world so full of misery?

Have him explain this phenomenon:

The BA sometimes hangs out at The Straight Dope message board too.

Does he believe that, for instance, electrical charge is quantized?

Frankly, there's a pretty good chance that he's not rational enough to have a conversation, let alone an argument with.

I used too. They charge for it now, and I am morally opposed to that, so I didn't sign up.

Ah, the pay-for-play charge. Funny, I'd forgotten about that when I made the recommendation or I would've warned--someone else paid for me (long story).

I have to say that bodes well for the future of the BABB.

I suspect daver is right, but...

Charge quantization: Millikan oil drop experiment

Energy quantization: black body spectrum

Mass quantization: constancy of empirical molecular formulas. For that matter, the existence of compounds in the first place.

Interpenetration of matter: dissolve common salt in water, watch water level drop.

Or in my own area, the simple ability to do mass spectrometry.

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The Devil offered me power. I told him I preferred aperture.

Is this guy's name Sam5?

The things you miss in the undergrad lab when you're more worried about being done on time and getting the writeup done... I've done all of these things, and not once did I think of them as evidence for atoms. Then again, I sort of went into the experiments already convinced of their existance.

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"I'm making wheatloaf. It's like meatloaf, only with wheat"
"Isn't that just...bread?"

You can discuss anything in BABBling apart from R&P.

The simple proof of atoms is that they've been imaged through Bragg diffraction.

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Freedom For Fission A breath of fresh Iodine-131

I'll grant that Ut is right when he says my list is not direct evidence for atoms in our current understanding. But it does offer strong observational evidence for discontinuty of matter/energy. From which one may reasonably ask if there are pieces, how are they constructed? Then we get to spectra and charge ratios and coulombs to moles and such.

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The Devil offered me power. I told him I preferred aperture.