1
00:00:05,529 --> 00:00:07,387
You've probably heard of electrons and protons,

2
00:00:07,387 --> 00:00:09,761
the building block particles that make up atoms.

3
00:00:09,761 --> 00:00:12,137
But there are all kinds of other particles in the universe,

4
00:00:12,137 --> 00:00:15,095
and we have a pretty good idea of what they are and how they interact.

5
00:00:15,095 --> 00:00:18,622
But even our best theories struggle when it comes to big nasty questions.

6
00:00:18,622 --> 00:00:20,116
Like, where does mass come from?

7
00:00:20,116 --> 00:00:21,982
And what is dark matter made of?

8
00:00:21,982 --> 00:00:25,118
There may be a theory that can answer these questions at a stroke.

9
00:00:25,118 --> 00:00:28,987
It's elegant, mathematically speaking, but is it true?

10
00:00:28,987 --> 00:00:31,107
It's called "Super Symmetry".

11
00:00:35,061 --> 00:00:38,594
If you wanted to explain why all stuff in the universe behaves the way it does,

12
00:00:38,594 --> 00:00:41,822
you could do a lot worse than the so-called "Standard Model".

13
00:00:41,822 --> 00:00:43,692
Developed in the 1960's and 70's,

14
00:00:43,692 --> 00:00:47,214
it categorises all fundemental particles as either "leptons", like electrons,

15
00:00:47,214 --> 00:00:50,906
"quarks", the building blocks of protons and neutrons,

16
00:00:50,906 --> 00:00:55,738
or "force carriers", like photons, which transmit electric and magnetic force.

17
00:00:56,107 --> 00:00:58,416
The Standard Model is a triumph of modern physics,

18
00:00:58,416 --> 00:01:01,572
every particle the theory predicts has been observed in experiments,

19
00:01:01,572 --> 00:01:03,367
except for one.


20
00:01:03,367 --> 00:01:07,331
The Higgs boson, a force carrrier thought to give other particles the property of mass,

21
00:01:07,331 --> 00:01:09,754
has so far eluded direct detection.

22
00:01:09,754 --> 00:01:13,086
And what's worse, experiments suggest that if the Higgs boson exists,

23
00:01:13,086 --> 00:01:16,605
it would likely be way lighter than the simple Standard Model predicts.

24
00:01:17,589 --> 00:01:19,414
But all is not lost.

25
00:01:19,414 --> 00:01:21,945
Physicists can get around this problem with a little mathematical tweaking.

26
00:01:21,945 --> 00:01:25,614
Think of the Standard Model as an old school hi-fi stereo system,

27
00:01:25,614 --> 00:01:29,492
and the variables in the theory are like the knobs on the amplifier.

28
00:01:29,492 --> 00:01:32,998
To get the sound you want you can twiddle the various bass, mid and high levels,

29
00:01:32,998 --> 00:01:36,623
tweaking by tiny amounts until it sounds just right.

30
00:01:36,623 --> 00:01:39,721
That's fine for listening to [Led] Zeppelin records, but instead of just 3 knobs

31
00:01:39,721 --> 00:01:42,083
the Standard Model has almost 20.

32
00:01:42,083 --> 00:01:44,162
How would you know how to set them all?

33
00:01:44,162 --> 00:01:48,011
With no real physical reason for turning one know one way, and another the other way,

34
00:01:48,011 --> 00:01:52,377
it's all very arbitrary, and not how we'd like to think the universe actually works.

35
00:01:52,377 --> 00:01:54,562
It would be nice if there were a more elegant solution.

36
00:01:54,562 --> 00:01:59,676
As it turns out the theory of Super Symmetry allows the mass of the Higgs boson

37
00:01:59,676 --> 00:02:02,058
to be in the right range without fine tuning the math.

38
00:02:02,058 --> 00:02:05,639
It does so by introducing a whole new cast of particles to pair up with the ones

39
00:02:05,639 --> 00:02:07,453
we already know about.

40
00:02:07,453 --> 00:02:12,404
These super partners are like bizarre world versions of the Standard Model particles only more massive.

41
00:02:12,404 --> 00:02:15,662
And not only do they interact to solve the Higgs mass problem,

42
00:02:15,662 --> 00:02:18,307
they also provide a plausible explanation for dark matter.

43
00:02:18,307 --> 00:02:21,417
The mysterious mass that makes up the bulk of the universe.

44
00:02:21,417 --> 00:02:24,716
The problem is none of these super particles have been detected yet.

45
00:02:24,716 --> 00:02:28,723
Even by the Large Hadron Collider, which many thought would have found them by now.

46
00:02:28,723 --> 00:02:32,056
This doesn't mean Super Symmetry isn't true, but it leaves the door open

47
00:02:32,056 --> 00:02:34,914
for all kinds of other theories, from messier versions of the Standard Model

48
00:02:34,918 --> 00:02:37,433
to more exotic theories envoking extra dimensions.

49
00:02:38,033 --> 00:02:41,641
So far, with no Higgs boson and no super partners, the chance of having

50
00:02:41,641 --> 00:02:45,137
a simple theory to explain everything seems to be getting smaller.

51
00:02:45,137 --> 00:02:46,637
But that may be ok.

52
00:02:46,637 --> 00:02:50,560
After all, there's nothing that says the physical world has to follow elegant mathematical rules.

53
00:02:50,560 --> 00:02:54,634
As much as we might hate to admit it, it could be that even at its most fundamental levels,

54
00:02:54,634 --> 00:02:56,764
reality is just messy.