# In physics can particles be in two places at the same time?

Can a particle be in two places at the same?

### 10 Answers

- formengLv 64 months ago
According to the Copenhagen interpretation of quantum mechanics, the answer is yes.

- WhoLv 74 months ago
Have a look at the experiments carried out when particles are fired at a card with 2 slits

even when just 1 particle is fired at a time you STILL build up an interference pattern on the other side

this can ONLY happen when 1 particle interferes with another

BUT you only fired 1 particle at the card - so where did the other particle come from?

Problem is- when you try to see what happened you do NOT get the interference pattern

(on yes it HAS been demonstrated "jim"?

and "collapsing the wave function" is just a get out phrase to explain when what we see as a result differers from what we see when we try to observe what gave rise to the result;

not correct hoarseman

an explanation is that the cat is both dead and alive - but in 2 different universes

But when you open the box to look you "fix" the universe you are in and see the cat dead

but there is another "you" in the 2nd universe that fixes "you" in that universe who see the cat alive

- JimLv 74 months ago
First, I assume you meant can 1 particle be in 2 places.

Just when we say no, it's not possible at all, someone will show where it happens in some way.

So far I think it's safe to say no, it has not been demonstrated, but let's wait and see!

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- oldprofLv 74 months ago
For those who subscribe to the Copenhagen Convention...yes. [See source.] For those who reject the conclusions of that convention...no.

I personally think de Broglie, who rejected the interpretation of that convention, was correct. That is, the particle location is in one place, not two, at any given moment. But the uncertainty and observational results we get through, say, the split slit experiments, are due to pilot waves in space.time itself.

Source(s): The first is the Classic Copenhagen Convention, or CCC. equations predict the probability of what one will observe. Making an observation collapses the equation. That is, once you know which solution has been observed, you can disregard all the others. They Copenhagen v Many Worlds - Polyticks polyticks.com/psi/worlds.htm - cosmoLv 74 months ago
If you localize an electron to an exact position, its momentum becomes infinite, so it's not there anymore.

The function describing its possible positions is Fourier conjugate to the function describing its possible momenta, so if you squeeze one, the other expands.

- Jeffrey KLv 74 months ago
We must be very careful with our terms. An electron, or any quantum entity, is a wavefunction before it is observed. A wave is in many places at once, just like a water wave. When the electron is observed, its wavefunction collapses and it then becomes a particle. The particle is in only one place, never two or more.

- HoarsemanLv 44 months ago
The answer is No -- just as Schrodinger's cat was never both alive and dead .