New Scientist - 09.11.2019

9 November 2019 | New Scientist | 17

Electric cars

Technology Astrophysics

Sorry, sex won’t

start labour

Sex got you into this – can

it get you out? A review of

trials looking at whether

sex can induce labour has

found no evidence for this

commonly held view. In all,

the evidence from about

1500 women shows that

it makes no difference to

when labour starts (The

Journal of Sexual Medicine

doi.org/ddhs).

Smallest ever

black hole spotted

A search for black holes has

uncovered the smallest yet

seen at only 3.3 times the

mass of the sun. It is about

10,000 light years away

from Earth, where it orbits

a giant star about once

every 83 days. Despite its

mass, the black hole is only

about 20 kilometres across

• roughly the length of
  Manhattan in New York
  (Science, doi.org/ddht).

Cancer drug takes

aim at mutation

An experimental cancer

drug targets a genetic

mutation involved in a

range of common and rare

cancers, including some

colorectal and lung cancers.

In tests, the drug removed

tumours in eight out of

10 mice and shrank them

in two out of four people

(Nature, doi.org/ddhm).

Warm batteries key

to a very fast charge

OWNERS of electric vehicles may

soon be able to fully charge their

cars in just 10 minutes, thanks to a

new design that heats up batteries.

One offputting aspect of electric

cars is the length of time it takes to

recharge them. Ideally, we need

batteries that can reach 80 per

cent charge – which gives a range

of roughly 300 kilometres – within

10 minutes, says Chao-Yang Wang

at Penn State University.

At the moment, when lithium

ARTIFICIAL intelligence can play

the real-time strategy video game

StarCraft II so well that it is better

than nearly all human players.

The AI, called AlphaStar, was

developed by tech firm DeepMind.

It competed anonymously against

people in a series of online games

on the official StarCraft II game

server, Battle.net, and ended up

ranked in the top 200 players for

each of the leagues it was in.

In January, an earlier version of

AlphaStar beat two of the world’s

top professional players of the

same title, but at the time it was

given advantages, such as the

ability to see the entire game map.

To level the playing field, this time

AlphaStar was restricted to what

human players can see, stopping it

from completing actions in multiple

locations simultaneously, said Oriol

Vinyals at DeepMind in a press

conference. The number of actions

was also restricted, so it wasn’t able

to click at superhuman speed.

This version of AlphaStar was

then pitted against human players

in various locations. In the European

league, it was in the top 0.2 per cent

of approximately 90,000 players

(Nature, doi.org/ggb9jx).

“It’s an extremely impressive

achievement,” says Julian Togelius

at New York University. Donna Lu

ion batteries are charged rapidly,

there is a tendency for lithium to

form plate-like deposits on the

negative electrode’s surface.

This can shorten battery life.

Wang and his team suspected

they could minimise this problem

by first heating the battery to a

temperature too high to allow

lithium plating to form.

To test this, they took an

industrial battery and inserted

micron-thick nickel foils in a stack

of electrode layers. This structure

allows the electrode to heat in

less than 30 seconds, setting up

conditions for ions to move

Vast stellar blasts

mimicked on Earth

WHAT happens when a star

explodes? Surprisingly, the same

thing that happens when gas

explodes here on Earth.

For gas explosions to occur,

there needs to be a build-up of

pressure. Alexei Poludnenko at

the University of Connecticut and

his team wanted to find out how

this can happen in unconfined

spaces, such as in a type Ia

supernova, when a small star

called a white dwarf detonates.

Poludnenko and his colleagues

wondered whether there were

similarities between these events

and unconfined explosions on

Earth. To investigate, they ignited

a mix of methane and air in a lab

facility and measured the pressure

of the resulting explosion with

sensors, while also tracking the

speed of the flames. They then

compared this with a computer

simulation of a type Ia supernova.

They found that igniting the

gas mix created fast turbulence,

stirring up the flames and making

the burning more vigorous,. Once

the burning is fast enough, this

creates pressure so quickly that

it doesn’t have time to dissipate,

eventually causing a detonation.

The team says the same process

seems to be behind supernovae

(Science, doi.org/ddhr). LL

quickly into the negative

electrode without lithium plating.

Then, they tested how well

the cells worked when they

were charged at either 40°C,

49°C or 60°C, and compared

the performance with a control

battery charging at 20°C.

They found heating the

electrode to 60°C was best,

allowing the battery to recharge

through 2500 cycles without

forming lithium plates. That

is equivalent to 14 years of use

or around 750,000 kilometres

of driving, says Wang. (Joule,

doi.org/ddmh) RPS

AI conquers most players of

hit video game in a fair fight

CAIAIMAGE/PAUL BRADBURY/GETTY

ALPHASTAR

Really brief

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