4 . The more you meditate and achieve mindfulness, the better you’ll feel. There are many free meditation apps that offer guided sessions, calming playlists.

This app is simple and approachable for meditation beginners. Most of the free sessions focus on teaching the users how to meditate and easing them into the practice, while also acknowledging that meditation can be difficult. Yet to get into the really good stuff, you need to pay for the full membership.

The app offers a multitude of meditation bells and calming musical notes during self-guided meditations. Featuring a variety of professional instructors and courses, Insight Timer also offers more contents for free users than other apps. Although the free option is extensive, the premium version (高级版) offers courses, downloadable meditations, night mode, and daily insights.

The app groups all its free meditations together, so it’s easy to use it without paying. These meditations run from 5 to 30 minutes and are available for download, a feature that other apps typically reserve for premium members. The number of free contents, however, is limited and included mostly basics. The design of the app is also relatively plain.

A nice feature about Breethe is the calming background music that plays while the app is open, even without opening a meditation or music. Breethe offers a lot of sleep contents, including visualizations and bedtime stories. The app does offer a few 7-day courses for free, but the majority (1,000-plus meditations) is locked behind the paywall.

6 . Recently, as a journalist, I have published many stories about social media, privacy and artificial intelligence (AI), among other things. So when ChatGPT told me that my output may have influenced its responses to other people’s prompts (提示), I rushed to wipe my data from its memory. As I quickly discovered, however, there is no delete button. AI-powered chatbots never forget what they have learned, because they are trained on data sets including vast numbers of websites and online articles. As long as they exist on the Internet, they get to be remembered.

That means the likes of ChatGPT are possible to let out sensitive personal information, if it has appeared online, and that the companies behind these AIs will struggle to make good on “right-to-be-forgotten” regulations, which force organizations to remove personal data on request. It also means we are powerless to stop hackers (黑客) controlling AI outputs by planting misinformation or ill instructions in training data. All of these explain why many computer scientists are busy to teach AIs to forget. While they are finding that it is extremely difficult, “machine unlearning” solutions are beginning to appear. And the work could prove vital beyond addressing concerns over privacy and misinformation.

The new generation of AI-powered chatbots like ChatGPT, which produce text in response to our prompts, are underpinned by large language models. These are trained on mountains of data, most of which is scraped from the Internet. From this, they learn to spot statistical patterns, which means they can predict the likeliest next word in a sentence, producing fluent answers to our every question.

The trouble is that the way AI chatbots work means that when they learn something, it can’t be unlearned. This creates a significant problem when it comes to privacy, as Dr. Zhang made clear in recent research. He highlighted how difficult it will be for AI companies to obey the “right to be forgotten”, which the European Union declared a human right back in 2014.

9 . Los Angeles is home to a popular cycling culture. The following bike shops will help you see the city in a whole new light.

Los Angeles Bike Academy

Los Angeles Bike Academy is a bike shop with a critical mission: Provide resources and community for local underserved youth. Its initiative is its Earn-a-Bike program, where students spend time in the shop learning the basics of bike maintenance and running a store, and they graduate with their own bike. LABA also forms competitive cycling teams that race all around the country.

The Cub House

It’s a bike shop, a plant store and a nice place to wander through. It has something for everyone. Here you can play a game of ping-pong on the outdoor table, head into the mini greenhouse for a delicate plant, or just admire the vintage (老式的) cycling clothes hung on the walls. Finally, make sure to swing by the Cub House for the L. A. Invitational, a weekend party featuring multiple bike rides and a vintage car and bike show outside the store.

Frank’s

Some of the wildest bikes in L. A. are rolling out of Frank’s. The house specialty here is BMX, specifically luxury models with large 29-inch wheels. These bikes are as much fun to look at as they are to ride. Since 1992, Frank’s has found a business opportunity for itself as a destination for BMX builds and hard-to-find parts. The display counter has enough attractions to match a jewelry store.

The Bicycle Stand

This spacious store features classic vintage bikes. It’s worth making a trip to this store just to see their amazing collection. The store also specializes in vintage bike repainting and restorations. Besides, the Bicycle Stand team works on all kinds of rides, and the shop has a variety of refurbished (翻新的), ready-to-ride bikes for sale.