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Milky Way Is Being Pushed Across the Universe (cnn.com)
dryriver quotes a report from CNN: Our home galaxy, the Milky Way, is being pushed across the universe by a large unseen force, according to new research. Although it may not seem like a friendly gesture, the newly discovered Dipole Repeller is actually helping our galaxy on its journey across the expanding universe. Researchers have known that the galaxy was moving at a relative speed for the past 30 years, but they didn't know why. "Now we find an emptiness in exactly the opposite direction, which provides a 'push' in the sense of a lack of pull," said Brent Tully, one of the study authors and an astronomer at the Institute for Astronomy in Honolulu. "In a tug-of-war, if there are more people at one end, then the flow will be toward them and away from the weaker side." But this is no aimless journey of motion. Researchers have long believed that our galaxy was attracted to an area rich with dozens of clusters of galaxies 750 million light-years away, called the Shapley Concentration or Shapley Attractor. "We found a flow pattern reminiscent of streams of water that are organized by gravity to run downhill," Tully said. "In detail, we played a mathematical trick by inverting the sense of gravity to see where flows would terminate in this altered case. Flows ended at our Dipole Repeller."
Right! And what we call light bulbs are actually dark suckers.
You can joke if you wish, but in physics you may have heard of something called a "frame of reference," which specifies the default state you assume. That's not quite analogous to what TFA is doing, but it's something like that.
Newtonian physics assumes a default frame of reference that has no forces in it. Hence, we only talk about forces "existing" when they are non-zero.
But this "no forces" frame of reference doesn't really make sense when talking about the universe on large scales. Instead, the default state of the universe is a general curvature of space-time that galaxies exist within. You could perhaps think of it has a general "slope" on the rubber sheet model of spacetime. Or, if you insist on the tug-of-war analogy, the "default" state is with a certain level of tension. If you grew up as part of a "rope" within a universe like that, you'd probably develop a system of physics where the default "frame of reference" included tension forces pulling at you on both sides.
Anyhow, the "push" and "pull" and gravity doesn't quite make sense in terms of our normal analogy of grabbing onto something and physically pushing or pulling it. Rather, thinking of spacetime as curved, we change the slope. In the case of TFA, we have the default "slope" that pervades the universe, and previous research says our galaxy is moving in direction X more than the slope would suggest due to increased curvature in that direction. But it turns out there's also decreased curvature in another direction, which effectively decreases the threshold of the "default slope" in that direction.
If you lived as a "rope" in a continuous tug-of-war game since the beginning of time, which mostly had a default "tension" pulling at you from all sides... then you'd likely perceive a decreased tension as a "push" too. Since the whole "push/pull" thing is a bad analogy for gravitational spacetime curvature on a cosmic scale anyway, I'm not sure why everyone here is making fun of a bad analogy while upholding their bad analogy. They're both seriously flawed in this case.