The Pauli Exclusion Principle simply states that a fermion cannot exist twice in a quantum state.  At a more basic level (also known as, the level I’m at and I’m a fifth year chemistry student), two electrons with the same spin cannot be in the same quantum state.   They have to be of opposite spins.

Figure 1 is hydrogen. Yeah, it’s pretty boring.  One electron in the 1s orbital.  That electron could be pointing up or down (ie, of either spin), but by convention we write it upwards.

Figure 2 is helium… sort of.  In this example, two electrons are in the 1s orbital.  However, both electrons have the same spin.  That is what the Pauli Exclusion Principle says we cannot do.

Figure 3 is also helium.  Two electrons in the 1s orbital however, the second is pointing downwards, thus signifying a spin in the other direction.  That is the correct way of drawing the 1s orbital.

(The electrons can also be drawn on top of the line.  In fact, I had one chem prof who wanted them drawn that way and a different chem prof who wanted them to be drawn through the line.  Clearly, I like the second chem prof more.)

Now, back to the regularly scheduled tv discussion.

Last Thursday, Fringe made a grave mistake in science.

Yes, Fringe is all about mistakes in (fake) science.

This mistake, however, holds the singular claim (for this show) of pissing me off.

The mistake?  Nina Sharp was explaining to Olivia about why the two universes cannot be brought together – one will inevitably be destroyed.

Yes, that’s a pretty common theory and it always shows up in science fiction.  In fact, I have absolutely no problem with that – it’s effing theoretical physics so do whatever the hell you want.

Just don’t mutilate quantum mechanics whilst you do so.

You see, Nina’s reasoning for why two universes can’t exist at the same time was ‘you know the Pauli Exclusion Principle?’ and then smush the two snow globes together and one breaks whilst the other is perfectly intact.  Immediately, I hit the pause button on my dvr and yelled at the tv ‘but that’s not what the Pauli Exclusion Principle says!’  I also wished that I was watching this live so I could get on the twitters and tweet about it, but my twitter addiction is not the topic of today’s blog.

While the wiki article on the Pauli Exclusion Principle is pretty technical and could almost imply that two of the same things cannot exist at the same time, you do have to remember that things on the quantum level do not apply to the macroscopic world.  Last I checked, my location wasn’t uncertain.  I’m really damn sure that I’m sitting in front of my computer writing this blog entry.  However, that electron?  Yeah, that one over there.  Well, it might not actually BE over there.  It could be here.  Or there.

And somehow I got onto Heisenberg’s Uncertainty Principle and the Born Interpretation instead of the Pauli Exclusion Principle.

Right.

Well, I am in a class about quantum mechanics right now.

The Pauli Exclusion Principle simply states that a fermion cannot exist twice in a quantum state.  More generally, two electrons with the same spin cannot be in the same quantum state.   They have to be of opposite spins.

Figure 1 is hydrogen. Yeah, it’s pretty boring.  One electron in the 1s orbital.  That electron could be pointing up or down (ie, of either spin), but by convention we write it upwards.

Figure 2 is helium… sort of.  In this example, two electrons are in the 1s orbital.  However, both electrons have the same spin.  That is what the Pauli Exclusion Principle says we cannot do.

Figure 3 is also helium.  Two electrons in the 1s orbital however, the second is pointing downwards, thus signifying a spin in the other direction.  That is the correct way of drawing the 1s orbital.

(The electrons can also be drawn on top of the line.  In fact, I had one chem prof who wanted them drawn that way and a different chem prof who wanted them to be drawn through the line.  Clearly, I like the second chem prof more.)

So, yeah, absolutely nothing to do with two universes colliding.

Great job on the science there Fringe.  Great job.

At least Stargate made up a nonsense reason for why two people from different universes can’t exist in one universe at the same time.  Entropic Cascade Failure ftw!

Long story short?  If you’re going to make up science, make up science.  Don’t try to manipulate actual scientific principles to suit your own needs.