Will traveling to the stars be possible?

Will interstellar travel be possible? At the current level of our technology, the answer is clearly no. Will it be possible in the future? It is always dangerous to make predictions: reality often strays from what was supposed to happen. But it doesn't look like interstellar travel is going to become feasible anytime soon. Of course, in the scientific literature, both serious and imaginative, various methods have been proposed, some of which we’ll review in this and future posts, by analyzing the relative probabilities of each one.

Many writers consider interstellar travel the next frontier of human spread, and the only guarantee to avoid our extinction, either accidental, if a cosmic catastrophe occurs, or caused by ourselves with a nuclear war. The problem is, a trip to the stars would be much more difficult than planet exploration in the solar system. Apart from the sun, the closest star to us is 4.27 light-years away, just over 40 trillion kilometers. With our current technique, speeds of the order of one million kilometers per day can be reached, so a trip to that star would last more than one hundred thousand years. Taking advantage of the gravitational pull of giant planets, like Jupiter, it would be possible to triple the speed, but even so we are talking about tens of thousand years.

Super-accurate Innumeracy

A.K. Dewdney

Between 1984 and 1991, A.K. Dewdney authored numerous articles in the section on Mathematical Games of Scientific American. He was one of the successors to Martin Gardner, most famous contributor of that section. Dewdney is also the author of an amazing book, The Planiverse (1984), which belongs to the same genre of mathematical fantasy as Edwin Abbott's Flatland, published just a century earlier.

In the previous post I offered a few examples of innumeracy taken from A.K. Dewdney’s book 200% of Nothing. In this book, Dewdney points out, among many others, two very frequent mathematical mistakes. The first consists in giving so few digits of a number that it loses all usefulness (he calls those numbers nums, to indicate that they are not full numbers, as they are not complete). The second mistake is the opposite: giving too many digits of a number, beyond what is necessary or makes sense. He calls unnecessary digits dramadigits, as they only serve to give the particular number a more dramatic look.

Let's look at an example from Dewdney's book:

Innumeracy

Douglas Hofstadter

Douglas Hofstadter, the author of the book Gödel, Escher, Bach, an Eternal Golden Braid, coined the word innumeracy, by analogy to the word illiteracy, to mean the lack of mathematical knowledge affecting a large part of the population.

Let's look at an example of innumeracy proposed by A.K. Dewdney in his book 200% of Nothing:

A man finds a $5 bill, puts it in his pocket and thinks: "As I have a $10 bill in my other pocket, I just won 50%." When he arrives at home, he discovers that he has lost the $5 note he had found. He then thinks: “As I had $15 and have lost $5, I have suffered a 33% loss. As previously I had won 50%, overall I have won 17%.”

Towards a reasonable use of COVID vaccines

There is a lot of controversy regarding the use of vaccines against COVID-19. Although they are very varied, the reactions to this problem can be classified into three large groups:

1.     Some (especially governments) are frankly in favor of everyone getting vaccinated.

2.     Others (usually specific individuals) openly oppose vaccination, either because they deny that the disease exists (deniers), or because they doubt the usefulness of vaccines, or because they consider them dangerous.

3.     A third group is in favor of the conscious and reasoned use of vaccines, but opposes compulsory vaccination, considering that such compulsion would be a violation of individual freedom and human rights.