Iran Strikes, Quantum Gravity, and the Keys to Romance

Good morning, it's Thursday, Sept. 3. We're covering the latest military strikes in Iran. First time reading? Join over 4.7 million insatiably curious readers. Sign up here.

Also in today's Digest: Einstein's equivalence principle applies at the quantum level (Need To Know), a new trailer for HBO's "Harry Potter" series (Sports, Ent., & Cult.), do GLP-1s slow aging? (Sci. & Tech.), how to not break up (In-Depth), and much more.

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 Need To Know 

Iran Strikes Escalate

Iran's foreign ministry accused the US of a war crime yesterday after shrapnel from a US missile hit a home hosting a wedding in Kuhestak, east of the Strait of Hormuz. The attack reportedly killed four people and wounded over 60 (see aftermath via YouTube, warning—sensitive).

US Central Command said it struck Iranian military targets along the country’s southern coast Tuesday to counter Tehran’s attacks on commercial ships and US forces. The attacks resulted in 14 other fatalities. Iran responded by targeting US military bases in Jordan, Iraq, and Kuwait. Most of the missiles and drones were intercepted, and no casualties were reported as of this writing. The exchange ended a monthslong pause in military action, during which the US sought to isolate Iran through economic sanctions. 

Meanwhile, the USS Abraham Lincoln docked in Thailand yesterday for a port call after 286 days at sea (see previous write-up). The roughly 5,000-person crew will remain there until Sunday, then return to San Diego.

Meta Glasses Crackdown

Meta announced new measures yesterday to block people using its AI-powered smart glasses from filming others without their knowledge. The effort comes as demand for Meta Glasses has skyrocketed, alongside a wave of videos showing men harassing women in public.

The company’s partnerships with Ray-Ban and Oakley have succeeded where other smart glasses endeavors have failed: Last year, Meta sold more than 7 million pairs—more than triple the 2 million sold in 2023 and 2024. The market has skewed young and male (see demographics), with Meta accounting for roughly 82% of global sales. However, some have criticized how easy it is for users to film people without their consent, including by covering up a light indicating recording. Now, Meta says cameras will be disabled if the glasses detect the light has been covered.

Apple and Snap are developing competing products amid predictions the sector will grow more than 60% by 2029. Google is also reentering the market, years after the failure of Google Glass (what went wrong?).

Einstein Theory Prevails

A falling quantum object is subject to the effects of gravity, a new study found yesterday. The finding for the first time confirms a decades-old prediction by Albert Einstein, aligning with his broader theory of gravity.

Physicists sought to probe whether Einstein’s equivalence principle—whereby objects undergo weightlessness in free fall—applies on a quantum level (see 101). To test the question, they used an apparatus that split a quantum wave associated with an atom into two paths, holding one still while projecting the other into free fall. After the experiment, interference between the waves allowed researchers to record a tiny difference in quantum phase aligning with calculations anticipated by Einstein’s theory of gravity. The finding marks the first direct measurement of its kind and suggests that the equivalence principle continues to apply at the quantum level.

While novel, the study does not reconcile the fields of quantum and classical physics. Learn about some of the differences here.

 In The Know 

Science & Technology

> Astronomers discover a 10-sided wave pattern in clouds above Saturn’s south pole via Hubble Space Telescope, evoking the 1980 discovery of a six-sided storm on Saturn’s north pole (More) 

> GLP-1s may slow aging in mice, as new research indicates older female mice that received semaglutide had a lifespan 12% longer than that of counterparts who did not get the obesity drug (More) | What is semaglutide? (More)

> DNA may influence around 7%-11% of your personality, according to a new study that found over 1,200 genetic variants associated with traits like extraversion and agreeableness (More) | Why do personality tests seem accurate? (More, w/video) 

Business & Markets

> US stock markets close up (S&P 500 +0.5%, Dow +0.6%, Nasdaq +0.5%) (More) | Southwest Airlines to debut airport lounges in Austin, Baltimore, Honolulu, and Nashville (More)

> Google avoids breakup of ad-tech business after judge rejects forced sale; tech giant faces new rules designed to increase competition in online advertising (More) | Uber to cut 10% of its workforce, or about 3,300 people (More)

> Chevron to invest over $7B in Venezuela over five years, aiming to more than double oil production to roughly 600,000 barrels per day—more than half Venezuela's current output (More) | The rise and fall of a petrostate (More) 

Politics & World Affairs

> Jury in Lindsay Clancy case tells judge it is deadlocked again, prompting the judge to read "Tuey-Rodriguez" instructions; scroll to read (More) | What happens in the event of a mistrial? (More) 

> Justice Department requires states to report undocumented immigrants in order to receive federal funding for low-income residents (More) 

> New York City temporarily bans use of AI in public school classrooms through eighth grade (More) | See teachers' perceptions of AI in K-12 classrooms (More)

In-Depth

> The Bleeding Hearts

The Atavist | Matthew Wolfe. In 2013, two thieves pulled off the largest armed robbery in Austrian history, disappearing with nearly $4M. Police soon discovered one of them was a former cop. His motive was hard to believe. (Read) 

> The Science of Staying Together

Big Think | John Gottman, Julie Gottman. For decades, two psychologists brought couples into a lab and watched them fight, connect, and fall apart. They discovered a handful of behaviors that could reveal which relationships were built to last. (Watch) 

When to hit the road (and when not to) this Labor Day weekend.

How to spot the International Space Station ​​before it's gone.

The 2026 Audubon Photography Award winners revealed.

A lion, tiger, and bear became best friends.

Where to travel for every decade of your life.

CLEAR, PreCheck, Global Entry: Which do you actually need?

Thousands of people are paying this man to draw their pets badly.

How a record player turns grooves into sound.

How many flips could you do into a lunar swimming pool? (w/video)

Clickbait: Baseball player takes "hugging it out" literally. (w/video)

Historybook: Treaty of Paris signed, ending American Revolutionary War (1783); Pulitzer Prize-winning journalist Marguerite Higgins born (1920); Author Malcolm Gladwell born (1963); Football coaching legend Vince Lombardi dies (1970).