Multiverse Debate with Penrose and Kaku

The recording of a debate I did with Roger Penrose and (virtually) Michio Kaku in May about the multiverse is now available on YouTube. I went away rather disturbed about how confidently Kaku spreads scientifically unsound statements.

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8 Billion People on The Planet

According to estimates from the UN, the population of our planet crossed the 8 billion mark yesterday. Is it good or bad if the world population increases? The brief summary is that at the moment overpopulation is not the biggest problem the world has. We looked at it in this video.

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New Claim that We Can Test Inflation In the Early Universe

A new paper proposes to test whether the early universe underwent a phase of rapid expansion called inflation by searching for a thermal graviton background that should be absent if inflation was correct. The problem with this idea is that (a) the signal is too small to measure anyway (now and in the foreseeable future) and (b) it’s totally possible to find models for inflation in which this background would be present. You can find an (uncritical) summary here. 

For this week’s video, we have looked at the data on testosterone levels in men and found that it’s indeed correct that they have been falling in the past decades. Why is that? No one really knows, but we look at some of the reasons that scientists have proposed.

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Existential Physics: The Big Questions Raised by Modern Physics

A contrarian scientist wrestles with the big questions that modern physics raises, and what physics says about the human condition. Order it here today!