Tag Archives: New Scientist

What is time? The mysterious essence of the fourth dimension | New Scientist

The true nature of time continues to elude us. But whether it is a fundamental part of the cosmos or an illusion made in our minds has profound implications for our understanding of the universe

Physics 15 June 2022, By Richard Webb

Skizzomat

WE ARE BORN; we live; at some point, we die. The notion that our existence is limited by time is fundamental to human experience.

We can’t fight it – and truth be told, we don’t know what we are fighting against. Time is a universal whose nature we all – and physicists especially – fail to grasp. But why is time so problematic?

“If we had a really good answer to that question,” says Astrid Eichhorn, a theoretical physicist at the University of Southern Denmark in Odense, “then it wouldn’t be so problematic.”

On a certain level, time is simple: it is what stops everything happening at once. That might seem flippant, but it is at least something people can agree on. “The causal order of things is really what time is all about,” says Eichhorn.

Viewed this way, the existence of time can be interpreted as a necessary precondition for the sort of universe where things lead to other things, among them intelligent life that can ask questions, such as “what is time?”.

Beyond that, time’s essence is mysterious. For instance, why can things only influence other things in one direction in time, but in multiple directions in the three dimensions of space.

Most physical theories, from Isaac Newton’s laws of motion to quantum mechanics, skirt such questions. In these theories, time is an “independent variable” against which other things change, but which can’t be changed by anything else. In that sense, time exists outside physics, like the beat of a metronome outside the universe to which everything inside it plays out.

Source: What is time? The mysterious essence of the fourth dimension | New Scientist

Origin review: A genetic history of the Americas | New Scientist

By Michael Marshall, 26 January 2022

Art and arrowheads from the Americas before European colonisation
William Scott/Alamy Stock Photo

WHO were the first people to reach the Americas?

When did they get there, and how?

These are among the most mysterious questions in prehistory, and have long been studied using traditional archaeology: bones, artefacts and so on.

In recent years, however, the field has been revolutionised by genetic data. DNA from living people and preserved remains has both enhanced and transformed our understanding of the continents’ First Peoples (those who were on the continent before Europeans arrived) and how they got there.

Jennifer Raff is a genetic anthropologist at the University of Kansas who has been involved in many studies of ancient American DNA, so she is an ideal guide to the subject. Her book Origin bills itself as “a genetic history of the Americas”, and it largely delivers on that promise. The final third of the book, in particular, draws on genetic and archaeological evidence to tell the story as we see it now.

This section is a model of clear and nuanced explanation: Raff highlights the uncertainties and caveats, but doesn’t allow them to overwhelm the story.

Source: Origin review: A genetic history of the Americas | New Scientist

What is consciousness like for other animals and when did it evolve? | New Scientist

The conscious experiences of non-human animals, from whales and birds to octopuses and bees, are revealing fresh clues about when consciousness evolved and what it’s for

Life 7 July 2021

By David Robson

Each arm of an octopus could be independently conscious
Azoor Wildlife Photo/Alamy

Children know the fun of throwing a ball into the sea, only to watch the waves fling it back. Jennifer Mather and Roland Anderson at the Seattle Aquarium were surprised to find octopuses playing similar games. Their toy was a floating pill bottle, which they were free to ignore or explore as they wished.

Six of the aquarium’s octopuses soon lost interest, but two showed childlike curiosity, pushing it with their arms or shooting jets of water to move it against the tank’s current. It is hard to interpret this as anything other than play, which many researchers argue requires some form of conscious awareness.

Many animals exhibit behaviours similarly suggestive of an inner life. Conscious creatures may include our primate cousins, cetaceans and corvids – and potentially many invertebrates, including bees, spiders and cephalopods such as octopuses, cuttlefish and squid. The challenge, of course, is to understand how the inner lives of these creatures differ from our own.

Editor’s Note: Sorry, excerpt only, full article is behind a paywall…

Source: What is consciousness like for other animals and when did it evolve? | New Scientist

Climate emergency: The new science showing it’s make-or-break time | New Scientist

As climate talks ramp up ahead of the crucial COP26 meeting in Glasgow, new research on what our carbon emissions are doing to the planet paints a disturbing picture

Environment, 21 April 2021, By Michael Le Page

Pete Reynolds

SHALL we start with the good news or the bad news? The good news is that the world has made some progress in cutting the carbon emissions driving climate change.

The bad news is that it is by no means enough, and emerging research suggests that the impact of the emissions we are pumping into the atmosphere could be even greater than we feared.

“The science, if anything, has become more pessimistic,” says Stefan Rahmstorf, a climate scientist at the University of Potsdam, Germany. “The signs from the science are pointing towards more urgent climate action being needed.”

Source: Climate emergency: The new science showing it’s make-or-break time | New Scientist