the magic jump rope

The magic really begins at 1:30 ...
A different video with the same trick in a different setting is available also.
Do you have an idea how to explain what Xavier does?

emptiness and relative truth

Recently, Lubos wrote a blog post about feminism and bitcoin, which contains an obvious inconsistency that I find quite interesting only because it is shared by many others.

In the first paragraph he is angry with millenials, because "They don't have any respect for freedom, the free market, and democracy."
Further down he rants against bitcoin and argues that "the Bitcoin's intrinsic value is still zero and the Bitcoin may only be sold for those huge amounts because of the existence of the opaque bubble that fools all the people inside and prevents them from seeing the truth".
But the price of bitcoin is established on various exchanges providing liquid, free markets - so should we not respect those free markets?

I only point this out because many economists, investors and traders, who certainly consider themselves free market capitalists, make similar arguments: bitcoin is obviously evil, a fraud, a bubble or worse, with zero real value.
So how do they explain that bitcoin survived several crashes and trades at significant and rising multi-billion dollar valuations for several years already? And if bitcoin is indeed a "bubble" that will implode at some point soon in the future, would it not be even more embarrassing for a proponent of free markets as efficient allocators of resources?


The idea that all commodities and goods have an "intrinsic value" seems obvious and was the main assumption of Karl Marx.
But there is no such thing as "value" and "price" in physics, except in the heads of human beings.
This is true even for the most basic commodities, i.e. food. A vegan assigns a different value to a steak than I do.
Some futurists think insects will become a major source of protein; in this case the value of crickets will move from zero to wherever the CME will price cricket futures. (*)
On the other hand, asbestos was for decades a valuable commodity and a billion dollar industry was producing it. But its price moved quickly to negative values when it turned out to cause lung cancer.

And what is the value of a black square painted on a white canvas?

As for bitcoin, the obvious answer is that its value is whatever price one can currently get on one of the exchanges. As a free market capitalist I believe this price contains information and in particular a prediction about the desires and demands of human beings in the future. However, I don't think markets are fully efficient and certainly not perfect predictors. The large volatility of bitcoin prices indicates significant uncertainty and suggests that it would be foolish to bet a large fraction of one's net worth on it. Currently, my own best guess (worth less than 2c) is that the future value of bitcoin a few years from now is somewhere in between 800$ and 80,000$ but if there is any bias it would be to the upside. (x)

(*) It might be interesting to discuss this economic relationship: The more useful and important a commodity is for human beings, the lower its value and price.
The air that we all need to breath comes at a zero price. Water is cheap in most places and certainly much cheaper than e.g. old wine. Food costs money (except the nutritious insects), but notice that the more you pay for dinner in a fancy restaurant, the less food you actually get on your plate.
A useful car is much cheaper than a fancy race car and so on and so forth. Finally, the most expensive goods, made from expensive commodities like gold and diamonds, are also the most useless (but I could never convince my wife about that).
This relationship could explain why the oldest and therefore least sophisticated and useful cryptocurrency (bitcoin, compared to ethereum or litecoin) is also the most expensive.
The worst that could happen to the price of bitcoin would then be widespread acceptance and adoption ...

(x) In my case, one reason for bias is the fact that I was mining bitcoin in 2011 and therefore own some coins and I would appreciate if they keep appreciating in value.

added later: Cullen Roche about all that.

Btw if you want to know how bitcoin works, I recommend this video.

the magic of the tiny plunger

I found that watching Penn&Teller during my daily exercise is quite helpful. So I watched a lot of magic tricks in recent months and of course I try to come up with explanations. In case of the tiny plunger I actually have two different ideas, but I don't know if they are correct.
But how would you explain the trick?

Btw the trick begins at 1:45 if you want to save time and fast forward ...