We are Late in an Interglacial Cycle

The US NOAA agency has posted this amazing chart showing what is known about glacial periods. This is mainstream science, and not a skeptic site. Think of it as a more complete version of the

Hockey stick graph.

The yellow bars are interglacial periods. The larger white regions in between are glacial cycles, aka ice ages.

These cycles are driven by slow variations in the Earth's orbit.

These glacial–interglacial cycles have waxed and waned throughout the Quaternary Period (the past 2.6 million years). Since the middle Quaternary, glacial–interglacial cycles have had a frequency of about 100,000 years (Lisiecki and Raymo 2005). In the solar radiation time series, cycles of this length (known as “eccentricity”) are present but are weaker than cycles lasting about 23,000 years (which are called “precession of the equinoxes”).

Here are my amateur observations from the chart.

Long-term cosmological cycles are much more important that what humans have done so far.  

We are overdue for another ice age.

Current CO₂ levels are high, but the biggest increases were 10-15k years ago, long before humans could have influenced the climate.

As these slow variations appear to be exceptionally important for glaciation, climate, and life on Earth, the Earth's orbit must be finely-tuned for human life.

If the long-term trends hold up, we have more to fear from cooling than warming. However, if catastrophic greenhouse gas emissions cause runaway warming, then this chart tells us nothing about the future.

I am not a climate expert, and I do not know whether greenhouse gases are a problem. They probably are. I just want to understand the physics. It seems possible to me that the Industrial Revolution put out just enough CO₂ to postpone an ice age.

Veritasium Video explains Many Worlds

Veritasium makes a lot of truly outstanding videos, and I recommend the channel for any readers here. But it made one on Parallel Worlds Probably Exist. Here’s Why about a year ago, and it leaves me scratching my head:

In the 1950's Hugh Everett proposed the Many Worlds interpretation of quantum mechanics. It is so logical in hindsight but with a bias towards the classical world, experiments and measurements to guide their thinking, it's understandable why the founders of quantum theory didn't come up with it. Rather than proposing different dynamics for measurement, Everett suggests that measurement is something that happens naturally in the course of quantum particles interacting with each other. The conclusion is inescapable. There is nothing special about measurement, it is just the observer becoming entangled with a wave function in a superposition. Since one observer can experience only their own branch, it appears as if the other possibilities have disappeared but in reality there is no reason why they could not still exist and just fail to interact with the other branches. This is caused by environmental decoherence.

It leads up to an interview of Sean M. Carroll, a many-worlds believer.

The concepts are explained pretty well, with good graphics.

Carroll tells that many-worlds allows essentially anything to happen, such as him being USA President or an NBA champion, as long as it does not violate conservation of energy or some other such principle. He says that this is not so strange, because we should ignore low probability events. Also, if you believe in an infinite universe with eternal inflation or some such mechanism, then there could be infinitely many copies of yourself doing bizarre things in distant galaxies/universes anyway.

Whilte the video exposes these silly arguments, it does not counter them.

Talking about infinite doppelgangers in infinite unobservable universes is no more scientific that discussion how many angels can dance on the head of a pin.

Carroll's use of probability was unchallenged, but the many-worlds theory has no way to say that any universe is more probable than any other. So while it is reasonable to ignore low probabilities, as Carroll says, there is nothing in the theory to say that those bizarro worlds have low probability.

Quantum Supremacy Claim Retracted

Scott Aaronson has just retracted his blessing for Google's quantum supremacy claims.

Quantum supremacy is the idea that a quantum computer could compute something much faster than a classical computer. Aaronson's big idea was that a quantum computer could just sample outputs from a complicated quantum random number generator, and that would pass as quantum supremacy if the classical computer could not simulate it efficiently.

That is what Google did two years ago, and Aaronson was the journal referee who approved the claim of quantum supremacy.

Now some Chinese researchers have shown that they can simulate Google's output on a classical computer. Aaronson says the Google team claims that they can keep changing the benchmark until they find one that the Chinese cannot simulate. He does not believe them.

Aaronson does not go as far as saying that Google's quantum supremacy is all a big hoax, but that's what I get out of his post. Read it yourself.

I am waiting for the quantum computers to compute something that is demonstrably difficult. That has not happened, and may never happen.

The Invention of Zero

When was the zero invented? It appears to have been around 0 AD, except that there was no such year. The year after 1 BC was 1 AD. It did not reach Europe until about 1200 AD.

I would have said that modern mathematicians agree that zero is a natural number, but I find that the world's smartest mathematician disagrees. He likes multiplicative number theory, where zero is avoided. I am pretty sure all the logicians would say that zero is a natural number.

Here is a new video on the subject: Is Zero More Than Nothing? Introducing the Zero Project

Closer To Truth 358K subscribers

Like the domestication of fire and the invention of the wheel, the concept of zero changed the course of human history. Yet zero’s origin remains shrouded in mystery.

Closer To Truth and Robert Lawrence Kuhn explore the mystery with The Zero Project, a group of international researchers searching for evidence of the invention of the numeral zero. Join the global expedition with expert guides from across diverse cultures and a range of specialty fields. In the quest for zero, visit far-flung places lost in time: North and South Africa, Central America, the Middle East, South-, Southeast, and Far East Asia.

Learn more about the project at www.zerorigindia.org

The invention of the numeral 0, and the number 0, seem like two different things. The numeral 0 was invented to allow base 10 numeric representation, like 100, a huge advance over Roman numerals. The number 0 is for the quantity 1-1.

I don't know how anyone can think clearly about anything, without the concept of zero.

The video says emptiness is important in Indian philosophy.

No Nobel Prize for Bell Test Experiments

Dr. Bee wrote:

I think a Nobel prize for the second quantum revolution is overdue. The people whose names are most associated with it are Anton Zeilinger, John Clauser, and Alain Aspect. They’ve been on the list for a Nobel Prize for quite some while and I hope that this year they’ll get lucky.

Many have been predicting Nobel prizes for these guys. And previously for David Bohm and John Bell, but they are now dead. See Bell test, for a survey of this work.

They have been passed up again this year.

My guess is that the explanation is that they do not give prizes for merely confirming existing knowledge. These experiments had the potential of disproving quantum mechanics, and that is what was driving the work by Bell and others. But they just confirmed the 1927 theory.

They say these experiments prove how strange quantum mechanics, because they show that it cannot be replaced by a local hidden variable theory. But again, that has been the consensus since about 1930. A Nobel prize for this would be like a prize for demonstrating energy conservation.

Some say that the Bell ideas provoked a lot of thinking about quantum information, "it from bit", and maybe even quantum computing.

But the maybe oddest thing to have come out of this is quantum teleportation. Quantum teleportation allows you to send quantum information with entangled states, even if you don’t yourself know the quantum information. ...

Quantum technologies have a lot of potential that we’re only now beginning to explore.

Dozens of Nobel prizes have been given for quantum theory. I just don't see quantum teleportation as important or interests, either theoretically or practically.

A Theory is a Hypothetical Explanation

I occastionally see science popularizers made a big point about the meaning of the word "theory". For example, the American Museum of Natural History says:

In everyday use, the word "theory" often means an untested hunch, or a guess without supporting evidence.

But for scientists, a theory has nearly the opposite meaning. A theory is a well-substantiated explanation of an aspect of the natural world that can incorporate laws, hypotheses and facts. The theory of gravitation, for instance, explains why apples fall from trees and astronauts float in space. Similarly, the theory of evolution explains why so many plants and imals—some very similar and some very different—exist on Earth now and in the past, as revealed by the fossil record.

But you only hear this from those promoting biological evolution or climate change theories. Here is more typical scientific usage, from a recent Nature magazine podcast:

Theories is the right word for it, because no one is really sure. ... Recently there has been a new theory. ... two existing theories... [2:30]

That's right, scientists talk about competing theories all the time, and they certainly aren't all well-substantiated as they usually contradict each other.

There are also theories like String Theory, which have no substantiation, and do not even make any testable predictions.

Wikipedia is dominated by evolutionists and climate leftists who insist on defining:

In modern science, the term "theory" refers to scientific theories, a well-confirmed type of explanation of nature, made in a way consistent with scientific method, and fulfilling the criteria required by modern science. Such theories are described in such a way that scientific tests should be able to provide empirical support for it, or empirical contradiction ("falsify") of it. Scientific theories are the most reliable, rigorous, and comprehensive form of scientific knowledge,[1] in contrast to more common uses of the word "theory" that imply that something is unproven or speculative (which in formal terms is better characterized by the word hypothesis).[2]

No, the theories on that Nature podcast are not well-confirmed, and String Theory is not described in a way to make it testable.

In Mathematics, a theory is a body of axioms, along with the theorems deducible from those axioms. They are usually computable and consistent, but may not match anything in the real world.