All the news media reported on Justice Ginsburg returning to the bench to hear oral arguments yesterday, February 19. Here is the story from the Washington Post
https://www.washingtonpost.com/politics/courts_law/ruth-bader-ginsburg-expected-on-bench-when-supreme-court-resumes-hearings/2019/02/19/b8ab182e-33c8-11e9-854a-7a14d7fec96a_story.html?utm_term=.5d8d2b588541I'm going to assume she was actually present, there would have been too many witnesses in the court room for her chair to have been unoccupied.
As for the "double" theories, I'll confess that there are few things in life I'm more skeptical about then these. I'll be 68 this June and have observed too many hoaxes: John Kennedy didn't die in Dallas and was living in the Caribbean, there were at one time published pictures of him in his 90's (he was 46 when he died); Elvis Presley didn't die in 1977 at age 42, and for many years there were innumerable Elvis sightings, all over the place and with pictures; There are the Sister Lucia of Fatima and the Pope Paul VI imposter scenarios, neither of which have been legitimately proven; Reported on this very forum was the theory that Barbara Bush snuffed her husband George H.W. just before she died April 17, 2018 at age 92, and that an imposter took his place until former President George Herbert Walker Bush's State Funeral. GHWB died November 30, 2018 at age 94.
Though a sceptic I never dismiss these theories out of hand and do review the information, but I've yet to be convinced. Just in case I need to reconsider my position I file (hardcopy, digitally, or mentally) this "data" where I also keep all the proofs for a flat earth or the moon landing hoax.
I don't claim to be exceptionally smart, if I were I would probable be actually retired right now and able to devote full time to caring for my 97 year old mother, rather than doing that and working 3 part time jobs on the side to cover expenses … in your charity please say an Ave for us. Yet, I grew up on a farm, took my university degree in Animal Science, worked in agriculture my entire career, and I now work part time for a funeral home, part time for the Red Cross teaching First Aid and CPR/AED skills, and in training to be a Master Gardener for the Cooperative Extension Service … my life has always been about the Scientific Method, and while he is not a canonized Saint I've always had an affinity with Abbot Gregor Mendel (St. Thomas Abbey in Morovia) who is credited with discovering the Divine laws of genetics.
Back to the topic: It seems apparent that someone sat in Justice Ginsberg's chair at the Supreme Court yesterday February 19. "If" that person was not actually Justice Ginsberg I have a very difficult time believing that people there who know her … clerks, pages, cafeteria, door, and security staff, other justices, and ESPECIALLY Justice Thomas and Justice Kavanaugh, would not now be saying something is "off" about it. I have to conclude that Ruth Bader Ginsburg is actually alive, and at least well enough to have shown up for work yesterday.