91色情片

IT HAS been almost a century since Fritz Zwicky first hypothesised the existence of dunkle materie 鈥� which translates to 鈥�dark matter鈥� in English. In 1933, looking at observations of galaxy clusters, he noted that there seemed to be a mismatch between the mass indicated by the motions of the galaxies and the mass measured by how much light the galaxies were radiating.

About 30 years later, Vera Rubin and Kent Ford used observations of stars orbiting their galactic centres to truly substantiate this mystery: there was more matter than we could see, suggesting a kind of invisible particle was actually dominating the motions of visible particles. Rubin and Ford鈥檚 papers on this topic were published over the 1970s, leading to an awakening in the 1980s: the dark matter problem was real, and it wasn鈥檛 going anywhere.

These timescales are large compared with a human lifetime. Having just turned 40, I still feel like 10 years is a long time! But 30 years is about half of many human lifetimes, and it was long enough that Zwicky didn鈥檛 get to see all of Rubin and Ford鈥檚 papers be published 鈥� he died in 1974. He didn鈥檛 live to see his hypothesis blossom into a major field of research.

The universe 鈥� beyond those close to Zwicky or superfans of his work 鈥� doesn鈥檛 care that he couldn鈥檛 witness dark matter become a compelling area of research. But, ultimately, we humans are the only part of the cosmos to care about the schedule on which we understand its details, and sometimes we get very emotionally invested in this process.

As a teenager, I read a book by Dennis Overbye 鈥� Lonely Hearts of the Cosmos 鈥� that featured Zwicky as one of many people involved in a dramatic debate about another cosmic mystery. This particular conundrum 鈥� how to measure how fast space-time is expanding 鈥� began with Edwin Hubble鈥榮 first measurements in the late 1920s and continues to this day.

In fact, the 鈥淗ubble tension鈥�, as the discrepancy between our measurements of this is now known, has been one of the hottest topics in observational cosmology in the past few years. It is a bit of a rabbit hole, too: every time we think we have answers, we get more questions. In 1998, two different teams realised the expansion of space-time was speeding up. So the problem is now different to the one Hubble thought he had identified in 1929.

This is the nature of science, at least in the realm of particle physics and cosmology. We think we know something, then our understanding is transformed by new information. We get new, interesting findings when we get them, which isn鈥檛 always when we want to get them. The cosmos, on the whole, doesn鈥檛 cater to our personal interests or timelines. We are the only part of the cosmos to do that.

This is personal for me. I work on the dark matter problem, and I do that daily while knowing that the questions I have may well be answered the day after I die. Or 200 years after I die. My personal timeline is, in many ways, irrelevant to when we humans work out the right model or get the right data. I try not to get emotional about this. This is the life I signed up for: to think about interesting ideas and hopefully find out whether any of them are correct. Emphasis on hopefully.

In particle physics, we got a bit spoiled during the 20th century. There are people older than me who came of age at a time when there were new particle physics discoveries, it seemed, every few years. A piece of data led someone to hypothesise a model with a new particle in it. People went looking for the particle, and they found the particle.

There are also people my age and younger who were raised on stories of these discoveries, with the promise that when we were older, we would experience a similar journey in science. As recently as 2012, we actually did, with the direct measurement of the mass of the Higgs boson. But the last major excitement before that was with the top quark in 1995 (if we aren鈥檛 counting dark energy, which we should, but I digress). It had been a while 鈥� if we are using an academic lifetime as our unit of measurement. And in 2022, we haven鈥檛 seen anything new.

Some people will have you believe this means particle physicists are wasting our time pushing forward using techniques that we know have worked in the past. 鈥淭hey just make things up for a living!鈥� they say, as if this is a bad thing. But I love this creative element of science, and it has been a historically important feature of the process.

In a time of rising fascism, I think it is important to be humble and embrace our creative side. There is so much we don鈥檛 know about the cosmos, and as Carl Sagan once said, without imagination, we go nowhere.