Clifford Stoll: The call to learn

Speaker

Clifford Stoll is an American astronomer and author. He is best known for his pursuit of hacker Markus Hess in 1986 and the subsequent 1989 book, The Cuckoo’s Egg, which details his investigation.

Summary

Clifford is a scientist – once a scientist does something once, it becomes engineering, and once that has been mastered it is operated by a technician. With that in mind, he can’t stay on the same project for too long (and throughout this talk, can’t stay on a single topic for long). His talk is written in a series of messy notes on his palm (written shortly before the talk). What he discusses is:

  • Tracing a hacking attempt on his network to the KGB.
  • To understand the future – don’t talk to a technologist or engineer or scientist – they can only tell you what things will exist. Instead talk to an experienced kindergarten teacher – they can tell you what society and the people will be like.
  • Klein bottles – he is fascinated with Moebius loops (one sided strips of paper – in the shape of a ring with a kink) and Klein bottles (one sided bottles, that exist inside themselves). He has made Klein bottles, and designed variations to drink wine from. In 4 dimensions, a Klein bottle should hold no fluids, but limited to 3 dimensions it can.
  • His mother’s passing and Robert Moog. Robert was a pioneer in electronic music, who invented the Moog synthesiser.
  • Children: Clifford teaches 8th grade science, but teaches it at a college level experimentation (skipping the high level calculus needed for college). They have measured the speed of light (within 25% – not bad for 8th graders). They also worked out how to measure the speed of sound – by using an oscilloscope, they found frequency and wavelength, then multiplied them. He showed how they did this on the studio, and were within 10m/s of the true number.
  • Running from police during the Vietnam War – he was chased around uni during riots by students, hit by teargas and started fleeing up a bell tower. He got to the top (distracted slightly by the pendulum) and looked below – seeing students with bricks and police fighting. To this background, he remembered bells are cast with inscriptions and read it

    “All truth is one in this light. May science and religion endeavour here for the steady evolution of mankind from darkness to light from narrowness to broadmindedness from prejudice to tolerance. It is the voice of life which calls us to come and learn”

My Thoughts

A very tough talk to summarise. I spent a while thinking “Lets see where he goes with this”, but not sure it was going anywhere. It is an insight into an eclectic and very entertaining man, flitting from topic to topic while deciding what he was going to talk about. Still, it was enjoyable – his excitable “mad scientist” persona was fascinating. He talks at high speed, which gets more amusing when you manipulate YouTube’s speed settings to make it even faster 🙂

For the curious, he gives you a lot to think about and research more.

Randall Munroe: Comics that ask “what if?”

Speaker

Randall Monroe – former engineer at NASA and most known for his webcomic at xkcd.com

Summary

Every week on his website xkcd.com, Randall writes a feature called ‘What If’ – where he answers questions using maths and displays them as an explanation interspersed with comics. For example, when asked what would happen when a baseball is thrown at the speed of light, he talks about the interactions with the air – superheating it to plasma and creating a mushroom cloud that would strike the batter. In his opinion, this would constitute a ‘hit by pitch’, and allow the batter to walk to first base (if it still existed).

Randall was asked how big Google’s data centres would be if all their data was stored on punch cards. Noone knows how much data Google holds, but Randall predicted it using estimates of the money Google has, or how many hard drives they use, or how big their data centres are, or how much electricity they used. He can use what he does know to improve the quality of guessing what he doesn’t. He predicted 10 exabytes of data, and perhaps another 5 exabytes of offline data stored in tape drives. A punch card holds about 80 characters, with about 2,000 cards in a box. 15 exabytes would cover the entire area of New England to a depth of 5km. A few weeks later he got a message from Google, consisting of punch cards. This is a puzzle, including a code, which gives them some equations, which Randall eventually cracks to get a message. The message was “No Comment”.

Randall enjoys maths, but not for it’s own sake. He likes using maths to take things he knows and then use them to discover what he could never know.

But sometimes maths cannot help. One of his user questions just contained the subject line “Urgent’ and the question “If people had wheels and could fly, how would we differentiate them from airplanes?”.

Michel Laberge: How synchronized hammer strikes could generate nuclear fusion

Speaker

Michel Laberge is founder and chief scientist of ‘General Fusion’.

Summary

Fossil fuels are currently our major energy source, since they are convenient and cost effective. Michel suggest nuclear power – it is energy dense, reliably produces power, and creates no CO2. Fission is currently the most common type of nuclear power, but fusion would be safer since the radioactive waste is very short term and there is no risk of meltdown. The fuel could be extracted from the ocean, and power us for billions of years.

Fusion is difficult to pull off – the 2 nucleii need to be thrown together so fast that they overcome their electrostatic repulsion, which can only be done at 150 million degrees. This heat is the limiting factor that makes fusion difficult. Some ways that have been proposed are

  • Magnetic fusion: charged plasma is suspended in a ring of magnets shaped like a donut, where it is heated to fusion temperatures.
  • Laser fusion: a ball of matter is compressed by lasers from all directions. As it compresses it heats quickly.

Plenty of people will dismiss fusion as purely theoretical, but fusion is progressing to become more and more practical. The research has been growing at a rate similar to Moore’s law – increasing by a factor of 10 each decade (ie: developing 10 times faster than the decade before it). The science needed to build a fusion reactor is now close, but political will is now slowing us down.

Fusion is criticised as being expensive – research costing about 1 billion dollars a year, but again Moore’s law was also expensive. The technology needed to get an internet-enabled smartphone cost 1,000 billion dollars. Subsidies to fossil fuel and renewable energy industries cost 650,000 billion per year. To solve the problem of fusion would be cheap and important by comparison.

Michel did not have the resources of the large labs, so needed a cheaper solution. He criticises laser and magnetic fusion as very large and expensive, and find it difficult to contain or use the fusion energy. The neutrons shoot at high speeds and high temperature and can damage the machines – it is as if containing and using the high energy neutrons was added as an afterthought rather than the goal.

Michel investigated Magnetised Target Fusion (MTF). In MTF, you fill a vat with liquid metal, then spin it to form a vortex in the middle. Pistons on the outside of the vat then compress the metal, where it gets hotter and begins fusing. It has advantages over laser and magnetic

  • the liquid metal absorbs the energy of fused neutrons, preventing damage to walls.
  • The liquid metal heats up, which can then be run through a heat exchanger and used to create energy.
  • Most of the energy comes from steam powered pistons, which is far cheaper than magnets or lasers.

Unfortunately MTF didn’t work: the plasma cools faster than the heat of compression, so it didn’t do anything. The improvement was to make the piston into an anvil and hammer. The pistons will accelerate and then smash into an anvil, to push all the energy into the liquid metal in one blow. This created some neutrons, which were enough for Michel to get $50 million and hire a larger team to develop the concept further. 14 hammers will be aligned around a small sphere, and the impacts need to be coordinated with precise electronics. If they fire 1 impact per second, it can produce about 100MW of electricity.

Fusion is coming – it has been done by large labs, and now smaller ones like Michel’s are showing it can be done.

 

Allan Adams: The discovery that could rewrite physics

Speaker

Allan Adams: MIT Associate Professor with focus on Theoretical Physics.

(Illustrated by Randall Monroe, of http://www.xkcd.com fame, a former NASA employee who now writes a science-themed webcomic)

Summary

If you look at the sky you see stars, but if you look further and further you see nothing. Beyond that nothingness is the afterglow of the Big Bang. This afterglow is nearly completely uniform at 2.7 degrees, but has cooled slightly in small patches (20 ppm). These tiny discontinuities are caused by Quantum Mechanical ‘wiggles’ during the Big Bang, that have been stretched across the universe.

Before the Big Bang, our universe was extremely dense like a metal bell. On March 17 something new was discovered. Like a metal bell, this original universe could be ‘rung’ by quantum mechanics, then it could produce gravitational waves (like the sound from a bell). Nowadays these gravitational waves have faded, but early on the waves caused small twists in the structure of light that we see. By searching the sky from the South Pole, researchers recently discovered these wiggles in the light coming from distant stars.

What this implies is that our universe is in a ‘bubble’. It is then possible that our ‘bubble’ is just one of many, even though we may never see the others.

further reading here: http://www.space.com/25100-multiverse-cosmic-inflation-gravitational-waves.html . The big key here was that in the first fractions of a second, the universe was expanding faster than the speed of light, with our ‘uniform’ universe an expansion of a very tiny point in the original tiny dense mass. Gravitational waves were an important feature of this model, but could never be identified until recently. If our universe condensed around one region and expanded outwards, it is likely others did likewise, hence the ‘bubble’ analogy.

Stephen Hawking: Questioning the universe

Speakers: Stephen Hawking – Physicist with University of Cambridge, known for the book “a brief history of time”. http://en.wikipedia.org/wiki/Stephen_Hawking

Summary

Until 1920s, people thought universe was static and unchanging. We then discovered that distant galaxies were moving away from us, which suggested originally everything was extremely close before expanding, hinting at a big bang. We have made progress understanding Maxwell’s equation and general relativity to understand how the universe has evolved, but struggled to describe the initial state of the universe. Under certain conditions, general relativity allows time to behave as another dimension, removing the distinction between time and space and allowing the universe to spontaneously create itself from nothing. We can use probability to simulate a number of different initial states which agree with observations. In this way, we have solved the creation of the universe.

Looking at extraterrestrial life, we believe life appeared spontaneously on Earth so it should be able to appear elsewhere. Algae fossils imply that life appeared on Earth within half a billion years of it becoming possible, which is short in the earth’s history. This implies that life can form relatively easily, but on the flipside we have not seen any aliens. From searches such as SETI, we can imply that there are no civilisations of our level of development within a few hundred light years.

Looking at the future, if we are the only intelligent beings in the galaxy we should ensure we survive and continue. But we are in a dangerous phase of history – our consumption of finite resources is increasing exponentially, as is our ability to change the world for good or evil. Our genetic code still carries selfish and aggressive instincts that may steer us astray. It will be difficult to deal with these problems to survive 100 years, not to mention thousands or millions. To ensure our survival beyond a hundred years we must expand into space. Stephen was later asked if he believes we are the only civilisation in the Milky Way at our intelligence level. He responds (after 7 minutes to compose the speech, edited out of the video) that he believes this is true, we would have found them otherwise. The other possibility is that our civilisation is in a late phase, and previous races of our technology level have not lasted long before destroying themselves.

Throughout his life, Hawking has tried to answer these 3 questions. He is grateful his disability has not prevented this, and it has given him more time to answer these questions.

 

Brian Cox: CERN’s supercollider

Speaker: Brian Cox

Length: 16:26

Rating 3 / 5

Summary

Brian very briefly discusses a number of topics in Physics

  • construction of the CERN supercollider
  • scale of the universe, and the subatomic particles within it
  • standard model, and the theoretical term in this ultimate equation that implies Higgs boson (the source of mass)

Critique

I might want to rewatch this talk. It had a lot of detail and raced through a lot of information. I think if I watched this a few times, I could get a basic understanding of subatomic physics. However, it felt slightly frantic and most of the detail went over my head. If you had some more grounding in physics, you might pick up more.

I feel like I might have enjoyed a more detailed and slower paced but smaller topic within subatomic physics.

However, the information in here could teach you a lot