2 . Until recently, gravitational waves could have been the stuff of Einstein’s imagination. Before they were detected, these waves in space time existed only in the physicist’s general theory of relativity, as far as scientists knew. Now, researchers are on the hunt for more ways to detect the waves. “The study of gravitational waves is booming,” says astrophysicist Karan Jani of Vanderbilt University in Nashville. “This is just remarkable. No field I can think of in fundamental physics has seen progress this fast.”

Just as light comes in a variety of wavelengths, so do gravitational waves. Different wave lengths point to different types of origins of the universe and require different kinds of detectors. Gravitational waves with wavelengths of a few thousand kilometers—like those detected by the United States, Italy and Japan—come mostly from pairs of black holes 10 or so times the mass of the sun, or from collisions of dense cosmic blocks called neutron stars (中子星). These detectors could also spot waves from certain types of exploding stars and rapidly moving neutron stars.

In contrast, huge waves that span light-years are thought to be created by orbiting pairs of bigger black holes with masses billions of times that of the sun. In June, scientists reported the first strong evidence of these types of waves by turning the entire galaxy (星系) into a detector, watching how the waves make slight changes to the timing of regular blinks from neutron stars throughout the Milky Way.

Physicists now hope to dive into a vast, cosmic ocean of gravitational waves of all sorts of sizes. These waves could reveal new details about the secret lives of exotic objects such as black holes and unknown parts of the universe.

Physicist Jason Hogan of Stanford University thinks there are still a lot of gaps in the coverage of wavelengths. “But it makes sense to cover all the bases. Who knows what else we may find?” he says. The search for capturing the full complement of the universe’s gravitational waves exactly could take observatories out into the moon, to the atomic area and elsewhere.

4 . As our lives become more closely connected with the digital age, it’s more important than ever to keep the spark of human connections, a key part of which is making small talk.     1     Here’s how to master the art of small talk.

The cornerstone of effective small talk lies in developing genuine interest. Genuine interest is about actively seeking to understand the other person, valuing their perspectives and appreciating the uniqueness they bring to the conversation.     2    

Small talk extends beyond spoken words; it includes the art of observation. As you engage in conversation, pay attention to the speaker’s body language, facial expressions and tone of voice.     3     Being familiar with them not only helps you navigate the conversation with sensitivity but also enables you to establish a deeper connection by respecting the slight differences of the other person’s communication style.

Actually listening and connecting with someone is essential for a conversation. By providing your undivided attention, you convey respect and interest in what the other person has to say.     4     Ask follow-up questions to show that you value their insights. This depth of engagement lays the foundation for a more meaningful connection.

At the heart of successful small talk lies the authenticity (真实性) of your engagement. Authenticity fosters a sense of trust and connection, making the conversation more meaningful and memorable. Avoid the temptation to project an image or use scripted responses.     5     In the world of small talk, authenticity is the key that unlocks the door to deeper connections and more fulfilling interactions.

5 . Most glitter(小发光物品), which is made up of tiny pieces of plastic, is a huge danger to the environment. “Everyone talks about the mountain of plastic floating in the ocean. You can grab empty bottles from the water, but with tiny pieces, it’s impossible,” says Victor Alvarez, a chemical engineer who sells an eco-friendly alternative to glitter.

In the early 2,000s, Alvarez worked for Mercedes-Benz in Germany, where he became fond of any technology that protected the environment. A few years after leaving Mercedes-Benz, he founded Blue Sun International in Miami, which makes specialty ingredients for the skin and hair care industries.

Glitter is a popular ingredient in cosmetics, such as eye shadows and lipsticks. So Alvarez began researching an alternative that didn’t contain plastic to make his products safer for the environment. That’s when he came across Ronald Britton Ltd., a company which had developed a plastic-free, biodegradable product called Bioglitter. It is made from regenerative cellulose(纤维素) sourced from hardwoods, primarily eucalyptus(桉树). Alvarez worked with the company to become the first retailer to sell Bioglitter in America. In 2018, he formed Today Glitter in order to sell the biodegradable glitter directly to consumers through its website.

Today Glitter sells two kinds of biodegradable glitter Bioglitter Sparkle and Bioglitter Pure. Both are almost plastic-free and can biodegrade in a short time. Meanwhile, they are as shiny as regular glitter. All these products are third-party tested by TÜV, an international organization that provides testing and certification for compostable (可降解的) and biodegradable products.

Despite its benefits, the hardwoods needed to make biodegradable glitter cause it to cost about twice as much as conventional glitter. A small glass container that contains just 6 grams of Bioglitter costs $10, while the same amount of regular glitter could cost at least half that amount. Alvarez expects the price will come down over time. He also expects the company’s sales to cross $1 million next year. But more importantly, Alvarez says, his main goal is to effect a meaningful change.

6 . My son Nile has left for university. Even Mother seldom _________ now that her grandchild is no longer around. My home has become so _________ in less than one month.

As a concerned mother who had little to do, I _________ Nile whenever I could. At first it was through emails. Occasionally I _________ the page of the university to learn about Nile’s campus life, and was filled with _________ to see his greetings: “Hi, Mum! So you’re on the net as well!” Since then I’ve been visiting the website regularly hoping to _________ my child.

Recently, our communicating way had another _________. Nile sent me all kinds of articles through instant messaging: novel, modern, funny... I read them _________, like a well-behaved pupil. Meanwhile, I had _________ feelings about that. The kid was __________ to learn something from me not that long ago, but he now becomes my teacher! After __________, I responded with the following email:

“Thank you, my son, for all interesting articles, though I feel confused about the change of our __________. Despite that, I’ll take it as a loving son’s __________ of his mother. He must be thinking his mother is still young and __________ enough to accept new things. That makes me feel proud.” Now in this way we share ideas, with the instant messages __________ each other.