A neutron walks into a bar and asks, "How much is a beer?" The bartender says, "For you, no charge."
A proton walks into a bar and says to the barman "I hear there's a special on beer?” The bartender asks, "Are you positive?"
An electron walks into a bar. "What a dingy place," he says. "Stop being so negative!" replies the barman.
A Higgs boson walks into a bar. The barman says, "We haven't seen many of you around here!"
An alpha particle tries to enter a bar, but can't get further than the door.
A beta particle enters a bar... through the window.
A gamma ray comes into a bar through the window, and goes out through the floor.
The tachyon orders a beer. A tachyon walks into a bar.
Some helium floats into a bar. The bartender says, "Get out! We don't serve your kind in this bar." The helium doesn't react.
A neutrino walks into a bar. The bartender says, "Get out! We don't serve any neutrinos in this bar." The neutrino replies, "Don't mind me; I'm just passing through."
A room temperature superconductor walks into a bar. The bartender says, "Get out! There are no superconductors allowed in this bar." The room temperature superconductor leaves without putting up any resistance.
Two bacteria walk into a bar. The bartender says, "Get out! We don't serve any bacteria in this bar. The two bacteria reply, "What? But we work here. We're staph."
Schrödinger's cat walks into a bar... and doesn't.
A parasite walks into a bar. The bartender says, "Get out! No parasites are welcome in this bar." The parasite responds, "Well, you're not a very good host."
An egg walks into a bar, thinks about having a beer, but then chickens out.
A young Tritium atom walks into a bar and orders a beer. "Sorry", says the barman, "but you have to be 18 years old to drink in here." "But that's more than half my life!" replies the Tritium.
A molecule of Carbon dioxide goes into a bar and orders a beer, looks down at all the bubbles, and says "Hi, guys!"
An infrared photon walks into a bar and says, "Is it hot in here, or is it just me?"