Heliumet ut av Hawking-ballongen

En liten oppdatering mens jeg fortsatt venter på pakken fra Amazon.

Ikke overraskende lander fysikeren Peter Woit etter å ha lest The Grand Design på at forlagets Hawking-hopp var mest hype.

Litt mer uventet er nok at Hawking synes å ha gitt opp jakten på en helhetsteori (den grandiose Theory of Everything) i fysikken.

Peter Woit er ikke den... største tilhengeren av strengeteori, noe som nok er grunnen til at hans anmeldelse viser samme evne til å skjære gjennom pretensjonene som Not even Wrong.

David Gross has in the past invoked the phrase “never, never, never give up”, attributed to Churchill, to describe his view about claims that one should give up on the traditional goals of fundamental physics in favor of anthropic arguments invoking a multiverse. Steven Hawking has a new book out this week, called The Grand Design and written with Leonard Mlodinow, in which he effectively announces that he has given up:

We seem to be at a critical point in the history of science, in which we must alter our conception of goals and of what makes a physical theory acceptable. It appears that the fundamental numbers, and even the form, of the apparent laws of nature are not demanded by logic or physical principle. The parameters are free to take on many values and the laws to take on any form that leads to a self-consistent mathematical theory, and they do take on different values and different forms in different universes.

Mens Hawking var svært så optimistisk i starten av sin karriere, hviler nå en slags ettertankens pessimisme over hans konklusjoner. Det virker dermed nærmest som et siste håp når han omfavner multiverset og det som kalles M-teori, selv om han i følge Woit tydeligvis sliter med å forklare hva dette egentlig er og hvordan det kan testes.

The book doesn’t even really try to explain what “M-theory” is, we’re just told that:

People are still trying to decipher the nature of M-theory, but that may not be possible. It could be that the physicist’s traditional expectation of a single theory of nature is untenable, and there exists no single formulation. It might be that to describe the universe, we have to employ different theories in different situations.

Men det er verre enn som så.

Hawking åpner boken med å se på hva som utgjør gode fysiske modeller. Han forklarer der at

A model is a good model if it:

1. Is elegant

2. Contains few arbitrary or adjustable elements

3. Agrees with and explains all existing observations

4. Makes detailed predictions about future observations that can disprove or falsify the model if they are not borne out.

Når han så lander på M-teorien, nevner han pussig nok ikke at denne ikke tilfredsstiller ett eneste av disse kriteriene.

The fact that “M-theory” satisfies none of these criteria is not remarked upon.

Woit kommenterer også medieoppslagene der Hawking (eller hans forlegger, får vi fortsatt håpe) gikk så bastant ut med at det ikke lenger var behov for Gud som en fysisk forklaring (altså en tanke som ikke er... lett å finne blant teistiske filosofer og teologer), Hawking hadde nemlig gjort dette overflødig med sin nye forskning.

Mens boken i stedet avslører at han verken har forstått teistisk tenkning eller har noe spesielt bunnsolid vitenskapelig å vise til.

Denne type dilletantisk oversalg kan ha vært mer til skade enn gagn - for britisk vitenskap.

There’s a new posting at physicsworld.com by Hamish Johnston that brings up the issue of the potential damage caused by this to the cause of science funding in Britain:

This morning there was lots of talk about science on BBC Radio 4’s Today Programme — but I think it left many British scientists cringing under their duvets.

Hawking explained that M-theory allows the existence of a “multiverse” of different universes, each with different values of the physical constants. We exist in our universe not by the grace of God, according to Hawking, but simply because the physics in this particular universe is just right for stars, planets and humans to form.

There is just one tiny problem with all this — there is currently little experimental evidence to back up M-theory. In other words, a leading scientist is making a sweeping public statement on the existence of God based on his faith in an unsubstantiated theory…

Physicists need the backing of the British public to ensure that the funding cuts don’t hit them disproportionately. This could be very difficult if the public think that most physicists spend their time arguing about what unproven theories say about the existence of God.

Det er uansett liten diskusjon om eller fravær av empiri på at Woits vurderinger ikke vil gi store overskrifter i media-Norge.

Eller få mer eller mindre nyateistiske bloggere til å trekke tilbake sine utspill fra forrige uke.