Drinking sediment is not harmful, but it is unpleasant, like having a mouthful of sand. To decant, be sure to hold the bottle upright long enough for the sediment to settle to the bottom. If you don’t have time for this, pour carefully and allow the sediment to settle in the glass.

For the vast majority, settling is not necessary. Sometimes I decant a really good wine if I know it’s too young. But the difference will not be obvious. Either way, it’s good.

In an episode of the HBO drama “Succession”, the character of Connor Roy once hyper-settling recommended, by pouring a red Burgundy in a blender to whip it full of air. “You can age your wine for five years in 10 seconds,” he said. It wasn’t a joke. The method has been promoted by Nathan Myhrvold in his book “Modernist Cuisine”. Personally, I would never subject a wine to such violence. It is a pleasure to follow its course as it evolves slowly and delicately in a glass over time. It is folly to believe that we can revive aging, except in the most marginal way. Don’t hesitate to beat your wine to submission, but don’t expect a miracle.

It depends. A wine made in the traditional way will be good at least several days after opening, maybe even longer. You won’t need any special equipment like vacuum pumps. Simply store the bottle in a cool place out of direct sunlight or in the refrigerator. A wine transformed, built and handled with technology and additives, will disintegrate much faster. Refrigerate and hope for the best.

The same goes for bubbles. If it is made with art and tradition, it can be kept for days without losing energy or effervescence. A poorly handled or overly handled wine will die. A good cork of sparkling wine is nice to have, but in a pinch, you can seal a bottle with foil, snug around the opening. Aluminum foil is far superior, although more expensive, than the popular trick of inserting a metal spoon, handle down, into the opening, who has been discredited.

Absoutely. Most reds are served too hot. The old advice that they should be served at room temperature was probably written by someone with a cold mansion. All reds should be at least slightly chilled, and reds that are simple thirst-quenches high in acidity can be served colder than that. In general, more tannic or complex reds should be served chilled but not cold. Yet what’s the worst that can happen if they are too cold? Let them warm up or wrap your hands around the bowl of the wineglass to add some warmth.

Indentation, or punt, is partly a matter of tradition and in some cases a necessity. Back in the days when bottles were made by hand, glassblowers would push the bottoms of bottles to make sure they would stand upright, without a piece of glass unbalancing them. The tray remains a custom, but it reinforces the structure of the bottles, in particular those used for sparkling wines, which undergo strong internal pressure due to carbonization. Not all bottles have cups. The tall, slender bottles traditionally used in Germany and Alsace have flat bottoms.