blog: cosmology question of the week
532. a googol of axions
Wednesday, April 10, 2024 at 12:00 AM CEST
531. scaling of density
Wednesday, April 3, 2024 at 12:00 AM CEST
530. measurables in field theories
Wednesday, March 27, 2024 at 12:00 AM CET
529. protect yourself against gravity
Wednesday, March 20, 2024 at 12:00 AM CET
528. tracing the determinant
Wednesday, March 13, 2024 at 12:00 AM CET
527. counting indices
Wednesday, March 13, 2024 at 12:00 AM CET
526. atmosphere of a neutron star
Wednesday, March 6, 2024 at 12:00 AM CET
525. buoyancy vs. gravity
Wednesday, February 28, 2024 at 12:00 AM CET
524. complex Maxwell-fields
Wednesday, February 21, 2024 at 12:00 AM CET
523. electrodynamics in n+1 dimensions
Wednesday, February 14, 2024 at 12:00 AM CET
522. quintessence made easy
Wednesday, February 7, 2024 at 12:00 AM CET
521. planetary orbits in 2d
Wednesday, January 31, 2024 at 12:00 AM CET
520. Kepler-problem in many dimensions
Wednesday, January 24, 2024 at 12:00 AM CET
519. repulsive classical gravity
Wednesday, January 17, 2024 at 12:00 AM CET
518. equation of state
Wednesday, January 10, 2024 at 12:00 AM CET
517. reciprocity
Wednesday, January 3, 2024 at 12:00 AM CET
516. gravitonics
Wednesday, December 20, 2023 at 12:00 AM CET
515. classical and relativistic waves
Wednesday, December 13, 2023 at 12:00 AM CET
514. duality breaking
Wednesday, December 6, 2023 at 12:00 AM CET
513. Lenz-rule in gravity
Wednesday, November 29, 2023 at 12:00 AM CET
512. most general classical theory of gravity
Wednesday, November 22, 2023 at 12:00 AM CET
511. weak field Lorentz-covariant gravity
Wednesday, November 8, 2023 at 12:00 AM CET
510. naive covariantization
Wednesday, November 1, 2023 at 12:00 AM CET
509. relativistic forces
Wednesday, October 25, 2023 at 12:00 AM CEST
508. inertial forces
Wednesday, October 18, 2023 at 12:00 AM CEST
507. dispersion of wave packets
Wednesday, October 11, 2023 at 12:00 AM CEST
506. differential geometry of curves
Wednesday, October 4, 2023 at 12:00 AM CEST
505. CQW holiday project: linear gravity
Wednesday, July 26, 2023 at 12:00 AM CEST
504. resonant gravitational waves
Wednesday, July 19, 2023 at 12:00 AM CEST
503. gravitational heating
Wednesday, July 12, 2023 at 12:00 AM CEST
502. dual tensors and the Bianchi-identity
Wednesday, July 5, 2023 at 12:00 AM CEST
501. invariants of gravitomagnetism
Wednesday, June 28, 2023 at 12:00 AM CEST
500. Lagrange density of weak field gravity
Wednesday, June 21, 2023 at 12:00 AM CEST
499. Galilean electrodynamics
Wednesday, June 14, 2023 at 12:00 AM CEST
498. a cornucopia of constants
Wednesday, June 7, 2023 at 12:00 AM CEST
497. massless Newtonian gravitons
Wednesday, May 31, 2023 at 12:00 AM CEST
496. superdeceleration
Wednesday, May 24, 2023 at 12:00 AM CEST
495. gravity is weird...
Wednesday, May 24, 2023 at 12:00 AM CEST
494. fluid mechanics in FLRW-models
Wednesday, May 17, 2023 at 12:00 AM CEST
493. relativistic dictionary
Wednesday, May 10, 2023 at 12:00 AM CEST
492. cosmological conservation
Wednesday, May 3, 2023 at 12:00 AM CEST
491. multipoles
Wednesday, April 26, 2023 at 12:00 AM CEST
490. incompressible flow
Wednesday, April 19, 2023 at 12:00 AM CEST
489. relativistic and nonrelativistic fluids
Wednesday, April 12, 2023 at 12:00 AM CEST
488. metric compatibility
Wednesday, April 5, 2023 at 12:00 AM CEST
487. forces and accelerations
Wednesday, March 29, 2023 at 12:00 AM CEST
486. perihelion shift in special relativity?
Wednesday, March 22, 2023 at 12:00 AM CET
485. relativistic chemistry
Wednesday, March 15, 2023 at 12:00 AM CET
484. uniqueness in general relativity
Wednesday, March 8, 2023 at 12:00 AM CET
483. continuity for charge and mass
Wednesday, March 1, 2023 at 12:00 AM CET
482. Weyl-tensor
Wednesday, February 22, 2023 at 12:00 AM CET
481. gravity, waves and ships
Wednesday, February 15, 2023 at 12:00 AM CET
480. Lambda and G in n dimensions
Wednesday, February 8, 2023 at 12:00 AM CET
479. fields as sources of gravity
Wednesday, February 1, 2023 at 12:00 AM CET
478. unusual shape of the Friedmann equations
Wednesday, January 25, 2023 at 12:00 AM CET
477. uniqueness of classical gravity
Wednesday, January 18, 2023 at 12:00 AM CET
476. gravitational focusing
Wednesday, January 11, 2023 at 11:42 AM CET
475. Hubble-scaling
Wednesday, January 4, 2023 at 12:00 AM CET
474. QM before Xmas: harmonics and hydrogen
Wednesday, December 21, 2022 at 12:00 AM CET
473. QM before Xmas: symmetry of the wave function on the slate
Wednesday, December 14, 2022 at 12:00 AM CET
472. QM before Xmas: unbounded operators
Wednesday, December 7, 2022 at 12:00 AM CET
471. QM before Xmas: canonical quantisation
Wednesday, November 30, 2022 at 12:00 AM CET
470. QM before Xmas: commutation
Wednesday, November 23, 2022 at 12:00 AM CET
469. QM before Xmas: Galilei-invariance
Wednesday, November 16, 2022 at 12:00 AM CET
468. QM before Xmas: Kepler meets Schroedinger
Wednesday, November 9, 2022 at 12:00 AM CET
467. QM before Xmas: degeneracy in hydrogen
Wednesday, November 2, 2022 at 12:00 AM CET
466. QM before Xmas: harmonic oscillator
Wednesday, October 26, 2022 at 12:00 AM CEST
465. QM before Xmas: time evolution
Wednesday, October 19, 2022 at 12:00 AM CEST
464. QM before Xmas: trace relations
Wednesday, October 12, 2022 at 12:00 AM CEST
463. QM before Xmas: squares of operators
Wednesday, October 5, 2022 at 12:00 AM CEST
462. CQW holiday project: weak field gravity
Wednesday, July 27, 2022 at 12:00 AM CEST
461. mapping shear flow
Wednesday, July 20, 2022 at 12:00 AM CEST
460. screening classical gravity
Wednesday, July 13, 2022 at 12:00 AM CEST
459. inertia of the Friedmann-equations
Wednesday, July 6, 2022 at 12:00 AM CEST
458. back to the basics 2
Wednesday, June 29, 2022 at 12:00 AM CEST
457. back to the basics
Wednesday, June 22, 2022 at 12:00 AM CEST
456. relativistic aging
Wednesday, June 15, 2022 at 12:00 AM CEST
455. Ehrenfest-symmetries
Wednesday, June 8, 2022 at 12:00 AM CEST
454. time-reversibility of quantum mechanics
Wednesday, June 1, 2022 at 12:00 AM CEST
453. Weyl-scaling
Wednesday, May 25, 2022 at 12:00 AM CEST
452. specific thermal power
Wednesday, May 18, 2022 at 12:00 AM CEST
451. Carnot-engine in cosmology
Wednesday, May 11, 2022 at 12:00 AM CEST
450. buoyancy and relativity
Wednesday, May 4, 2022 at 12:00 AM CEST
449. queezy relativistic feeling
Wednesday, April 27, 2022 at 12:00 AM CEST
448. Bohr's atomic model
Wednesday, April 20, 2022 at 12:00 AM CEST
447. ocean waves and gravity
Wednesday, April 13, 2022 at 12:00 AM CEST
446. Drake-equation
Wednesday, April 6, 2022 at 12:00 AM CEST
445. gravity and thermodynamics
Wednesday, March 30, 2022 at 12:00 AM CEST
444. Maxwell geodesics
Wednesday, March 23, 2022 at 12:00 AM CET
443. weak lensing of gravitational waves
Wednesday, March 16, 2022 at 12:00 AM CET
442. constants of Nature combined
Wednesday, March 9, 2022 at 12:00 AM CET
441. negative Hubble-constant
Wednesday, March 2, 2022 at 12:00 AM CET
440. electrodynamics in fewer dimensions
Wednesday, February 23, 2022 at 12:00 AM CET
439. Lovelock for electrodynamics?
Wednesday, February 16, 2022 at 12:00 AM CET
438. Galilei tries out geodesic deviation
Wednesday, February 9, 2022 at 12:00 AM CET
437. Newtonian geodesic deviation
Wednesday, February 2, 2022 at 12:00 AM CET
436. candle in a gravitational field
Wednesday, January 26, 2022 at 12:00 AM CET
435. rocket launch
Wednesday, January 19, 2022 at 12:00 AM CET
434. Lorentz-covariance of the large-scale structure
Wednesday, January 12, 2022 at 12:00 AM CET
433. multivariate Cauchy-distribution
Wednesday, December 22, 2021 at 12:00 AM CET
432. alternative Maxwell-density
Wednesday, December 15, 2021 at 12:00 AM CET
431. Einstein, Hilbert, Newton and Lagrange
Wednesday, December 8, 2021 at 12:00 AM CET
430. many famous names....
Wednesday, December 1, 2021 at 12:00 AM CET
429. retardation in electrodynamics
Wednesday, November 24, 2021 at 12:00 AM CET
428. determinant of the Schwarzschild metric
Wednesday, November 17, 2021 at 12:00 AM CET
427. electrical engineering in Lorentz-frames
Wednesday, November 10, 2021 at 12:00 AM CET
426. gauging in classical theories
Wednesday, November 3, 2021 at 12:00 AM CET
425. gauge transformations and gravity
Wednesday, October 27, 2021 at 12:00 AM CEST
424. measuring temperature
Wednesday, October 20, 2021 at 12:00 AM CEST
423. propagation of classical fields
Wednesday, October 13, 2021 at 12:00 AM CEST
422. locality and linearity
Wednesday, October 6, 2021 at 12:00 AM CEST
421. CQW holiday project: visible CMB
Wednesday, July 28, 2021 at 12:00 AM CEST
420. massive inflation
Wednesday, July 21, 2021 at 12:00 AM CEST
419. Hamilton-density as a gravitational source
Wednesday, July 14, 2021 at 12:00 AM CEST
418. accelerated cuckoo clock
Wednesday, July 7, 2021 at 12:00 AM CEST
417. CMB sail
Wednesday, June 30, 2021 at 12:00 AM CEST
416. waves in scalar- and vector-fields
Wednesday, June 23, 2021 at 12:00 AM CEST
415. oceans in relativity
Wednesday, June 16, 2021 at 12:00 AM CEST
414. tides and waves
Wednesday, June 9, 2021 at 12:00 AM CEST
413. cosmological constant
Wednesday, June 2, 2021 at 12:00 AM CEST
412. photon domination
Wednesday, May 26, 2021 at 12:00 AM CEST
411. cosmological melody
Wednesday, May 19, 2021 at 12:00 AM CEST
410. Mr. Turtur and cosmology
Wednesday, May 12, 2021 at 12:00 AM CEST
409. voyage to the centre of the Earth
Wednesday, May 5, 2021 at 12:00 AM CEST
408. horizon dynamics
Wednesday, April 28, 2021 at 12:00 AM CEST
407. gauging in classical gravity
Wednesday, April 21, 2021 at 12:00 AM CEST
406. relativistic and classical fluids
Wednesday, April 14, 2021 at 12:00 AM CEST
405. extended electrodynamics
Wednesday, April 7, 2021 at 12:00 AM CEST
404. NASER
Wednesday, March 31, 2021 at 12:00 AM CEST
403. alternative Bianchi-identity
Wednesday, March 24, 2021 at 12:00 AM CET
402. Maxwell's equations as 2nd order DEQ
Wednesday, March 17, 2021 at 12:00 AM CET
401. Weyl-curvature in cosmology
Wednesday, March 10, 2021 at 12:00 AM CET
400. cosmological constant
Wednesday, March 3, 2021 at 12:00 AM CET
399. coupling to matter
Wednesday, February 24, 2021 at 12:00 AM CET
398. antisymmetric tensors
Wednesday, February 17, 2021 at 12:00 AM CET
397. shortcut to black holes
Wednesday, February 10, 2021 at 12:00 AM CET
396. Ricci-tensor for classical gravity
Wednesday, February 3, 2021 at 12:00 AM CET
395. Weyl-tensor for classical gravity
Wednesday, January 27, 2021 at 12:00 AM CET
394. Weyl-tensor in GR
Wednesday, January 20, 2021 at 12:00 AM CET
393. gauging gravity
Wednesday, January 13, 2021 at 12:00 AM CET
392. curvature in FLRW
Wednesday, January 6, 2021 at 3:56 PM CET
391. symmetry and conservation
Wednesday, December 23, 2020 at 12:00 AM CET
390. Bianchi-identity and null-geodesics
Wednesday, December 16, 2020 at 12:00 AM CET
389. dispersion of gravitational waves
Wednesday, December 9, 2020 at 12:00 AM CET
388. vacuum solutions
Wednesday, December 2, 2020 at 12:00 AM CET
387. Weyl-tensor
Wednesday, November 25, 2020 at 12:00 AM CET
386. inertial motion in cosmology
Wednesday, November 18, 2020 at 12:00 AM CET
385. parallel transport
Wednesday, November 11, 2020 at 12:00 AM CET
384. multivariate distribution with units
Wednesday, November 4, 2020 at 12:00 AM CET
383. Hubble drag
Wednesday, October 28, 2020 at 12:00 AM CET
382. moving black hole
Wednesday, October 21, 2020 at 12:00 AM CEST
381. gravitational waves and their properties
Wednesday, October 14, 2020 at 12:00 AM CEST
380. dispersion-free propagation
Wednesday, October 7, 2020 at 12:00 AM CEST
379. CQW holiday project: Reissner-Nordstroem cosmology
Wednesday, July 29, 2020 at 12:00 AM CEST
378. colours of the rainbow
Wednesday, July 22, 2020 at 12:00 AM CEST
377. electromagnetic deviation
Wednesday, July 15, 2020 at 12:00 AM CEST
376. gravitational wave distortions
Wednesday, July 8, 2020 at 12:00 AM CEST
375. integral form of GR
Wednesday, July 1, 2020 at 12:00 AM CEST
374. scales in cosmology
Wednesday, June 24, 2020 at 12:00 AM CEST
373. partial and covariant derivatives
Wednesday, June 17, 2020 at 12:00 AM CEST
372. entropy conservation
Wednesday, June 10, 2020 at 12:00 AM CEST
371. nonrelativistic motion with gravity
Wednesday, June 3, 2020 at 12:00 AM CEST
370. relativistic and nonrelativistic motion
Wednesday, May 27, 2020 at 12:00 AM CEST
369. completeness of Newton's axioms
Wednesday, May 20, 2020 at 12:00 AM CEST
368. Newton's axioms from a relativistic point of view
Wednesday, May 13, 2020 at 12:00 AM CEST
367. fields at infinity
Wednesday, May 6, 2020 at 12:00 AM CEST
366. Reissner-Nordstroem gravitational wave
Wednesday, April 29, 2020 at 12:00 AM CEST
365. shearing of globular clusters
Wednesday, April 22, 2020 at 12:00 AM CEST
364. Kruskal-coordinates for RN-holes
Wednesday, April 15, 2020 at 12:00 AM CEST
363. relativistic motion
Wednesday, April 8, 2020 at 12:00 AM CEST
362. source of gravity
Wednesday, April 1, 2020 at 12:00 AM CEST
361. equations of motion in relativity
Wednesday, March 25, 2020 at 12:00 AM CET
360. geodesic deviation
Wednesday, March 18, 2020 at 12:00 AM CET
359. GR field equation in an unusual form
Wednesday, March 11, 2020 at 12:00 AM CET
358. lensing of the CMB
Wednesday, March 4, 2020 at 12:00 AM CET
357. decaying mode
Wednesday, February 26, 2020 at 12:00 AM CET
356. time-dependent couplings
Wednesday, February 19, 2020 at 12:00 AM CET
355. uniqueness of Planck-spectra
Wednesday, February 12, 2020 at 12:00 AM CET
354. CMB in the past and future
Wednesday, February 5, 2020 at 12:00 AM CET
353. weak lensing light cone
Wednesday, January 29, 2020 at 12:00 AM CET
352. PT-invariance
Wednesday, January 22, 2020 at 12:00 AM CET
351. acceleration in Newton-cosmology
Wednesday, January 15, 2020 at 12:00 AM CET
350. finite variance
Wednesday, January 8, 2020 at 12:00 AM CET
349. action for FLRW
Wednesday, January 1, 2020 at 12:00 AM CET
348. lost in space, again
Wednesday, December 18, 2019 at 12:00 AM CET
347. lost in space, part 2
Wednesday, December 11, 2019 at 8:23 PM CET
346. lost in space
Wednesday, December 4, 2019 at 12:00 AM CET
345. conformal transformation of weak fields
Wednesday, November 27, 2019 at 12:00 AM CET
344. cooling of an ideal gas
Wednesday, November 20, 2019 at 12:00 AM CET
343. exploding void
Wednesday, November 13, 2019 at 12:00 AM CET
342. massless bosons
Wednesday, November 6, 2019 at 12:00 AM CET
341. winter's coming
Wednesday, October 30, 2019 at 12:00 AM CET
340. inside a proton
Wednesday, October 23, 2019 at 12:00 AM CEST
339. alternative Wien-laws
Wednesday, October 16, 2019 at 12:00 AM CEST
338. equivalent twin paradoxon
Wednesday, October 9, 2019 at 12:00 AM CEST
337. relativistic Carnot engine
Wednesday, October 2, 2019 at 12:00 AM CEST
336. CQW holiday project: temperature measurement
Wednesday, July 31, 2019 at 12:00 AM CEST
335. adiabatic equation
Wednesday, July 24, 2019 at 12:00 AM CEST
334. Newtonian cosmology
Wednesday, July 17, 2019 at 12:00 AM CEST
333. Newtonian gravity in n dimensions
Wednesday, July 10, 2019 at 12:00 AM CEST
332. Yukawa-potential
Wednesday, July 3, 2019 at 12:00 AM CEST
331. hourglass in a gravitational field
Wednesday, June 26, 2019 at 12:00 AM CEST
330. coupling, gauges and external fields
Wednesday, June 19, 2019 at 12:00 AM CEST
329. gravitational waves
Wednesday, June 12, 2019 at 12:00 AM CEST
328. Roche limit for an elastic body
Wednesday, June 5, 2019 at 12:00 AM CEST
327. energy from Lagrange, and vice versa
Wednesday, May 29, 2019 at 12:00 AM CEST
326. classical gravity, but now with Lambda
Wednesday, May 22, 2019 at 12:00 AM CEST
325. classical gravity
Wednesday, May 15, 2019 at 12:00 AM CEST
324. more tensor contractions
Wednesday, May 8, 2019 at 12:00 AM CEST
323. tensor contraction
Wednesday, May 1, 2019 at 12:00 AM CEST
322. sense and sensibility
Wednesday, April 24, 2019 at 12:00 AM CEST
321. fermionic wave function
Wednesday, April 17, 2019 at 12:00 AM CEST
320. three great solutions to GR
Wednesday, April 10, 2019 at 12:00 AM CEST
319. Newtonian geodesic deviation
Wednesday, April 3, 2019 at 12:00 AM CEST
318. Poisson's equation with and without cosmological constant
Wednesday, March 27, 2019 at 12:00 AM CET
317. Newton's cosmological constant
Wednesday, March 20, 2019 at 12:00 AM CET
316. Kolmogorov and Smirnov
Wednesday, March 13, 2019 at 12:00 AM CET
315. accelerated charge
Wednesday, March 6, 2019 at 12:00 AM CET
314. listen very carefully
Wednesday, February 27, 2019 at 12:00 AM CET
313. slow-roll at nth order
Tuesday, February 19, 2019 at 11:00 PM CET
312. symmetric field tensor
Wednesday, February 13, 2019 at 12:00 AM CET
311. scattering gravitational waves
Wednesday, February 6, 2019 at 12:00 AM CET
310. orbit variations for LISA
Wednesday, January 30, 2019 at 12:00 AM CET
309. Planck units without Planck's constant
Wednesday, January 23, 2019 at 12:00 AM CET
308. digravic material
Wednesday, January 16, 2019 at 12:00 AM CET
307. Lagrange's error
Wednesday, January 9, 2019 at 12:00 AM CET
306. point masses and point charges
Tuesday, December 18, 2018 at 12:00 AM CET
305. Feynman's curtain rings
Tuesday, December 11, 2018 at 12:00 AM CET
304. Einstein and Rayleigh
Tuesday, December 4, 2018 at 12:00 AM CET
303. primordial gravity waves
Tuesday, November 27, 2018 at 12:00 AM CET
302. wave coincidence
Tuesday, November 20, 2018 at 12:00 AM CET
301. symmetry in relativity
Tuesday, November 13, 2018 at 12:00 AM CET
300. transversality of waves
Wednesday, November 7, 2018 at 12:00 AM CET
299. obtuse light cones
Wednesday, October 31, 2018 at 12:00 AM CET
298. description of light rays
Wednesday, October 24, 2018 at 12:00 AM CEST
297. scalar electrodynamics
Wednesday, October 17, 2018 at 10:18 AM CEST
296. boosting potentials and fields
Wednesday, October 10, 2018 at 12:00 AM CEST
295. Kirchhoff-rules and field theory
Wednesday, October 3, 2018 at 12:00 AM CEST
294. CQW holiday project: CMB in a lab
Wednesday, July 25, 2018 at 12:00 AM CEST
293. sound of silence
Wednesday, July 18, 2018 at 12:00 AM CEST
292. Lagrange's radio, part 2
Wednesday, July 11, 2018 at 12:00 AM CEST
291. Lagrange's radio
Wednesday, July 4, 2018 at 12:00 AM CEST
290. gravitational waves and Hubble expansion
Wednesday, June 27, 2018 at 12:00 AM CEST
289. relativity shootout
Wednesday, June 20, 2018 at 12:00 AM CEST
288. black hole merger
Wednesday, June 13, 2018 at 12:00 AM CEST
287. zeppelins and space ships
Wednesday, June 6, 2018 at 12:00 AM CEST
286. CMB gravitational shear
Wednesday, May 30, 2018 at 12:00 AM CEST
285. Hubble molecules
Wednesday, May 23, 2018 at 12:00 AM CEST
284. equivalence reloaded
Wednesday, May 16, 2018 at 12:00 AM CEST
283. conservation in gravity
Wednesday, May 9, 2018 at 12:00 AM CEST
282. deadly magnetars
Wednesday, May 2, 2018 at 12:00 AM CEST
281. pulsar magnetic fields
Wednesday, April 25, 2018 at 12:00 AM CEST
280. gravity of a magnetar
Wednesday, April 25, 2018 at 12:00 AM CEST
279. Hooke's universe
Wednesday, April 18, 2018 at 12:00 AM CEST
278. anisotropic equilibrium
Wednesday, April 11, 2018 at 12:00 AM CEST
277. Higgs and hydrogen
Wednesday, April 4, 2018 at 12:00 AM CEST
276. deflection of waves
Wednesday, March 28, 2018 at 12:00 AM CEST
275. Lissajous galaxy
Wednesday, March 21, 2018 at 12:00 AM CET
274. mildly relativistic particles
Wednesday, March 14, 2018 at 12:00 AM CET
273. cooling of atoms
Wednesday, March 7, 2018 at 12:00 AM CET
272. Eddington gravity
Wednesday, February 28, 2018 at 12:00 AM CET
271. electricity and magnetism
Wednesday, February 21, 2018 at 12:00 AM CET
270. FLRW curvature
Wednesday, February 14, 2018 at 12:00 AM CET
269. relative relativity
Wednesday, February 7, 2018 at 12:00 AM CET
268. celestial harmonics
Wednesday, January 31, 2018 at 12:00 AM CET
267. gravity from the Maxwell-field
Wednesday, January 24, 2018 at 12:00 AM CET
266. light and gravity
Wednesday, January 17, 2018 at 12:00 AM CET
265. charge and mass
Wednesday, January 10, 2018 at 12:00 AM CET
264. Maxwell invariants
Wednesday, December 20, 2017 at 12:00 AM CET
263. Einstein invariants
Wednesday, December 13, 2017 at 12:00 AM CET
262. Newton invariants
Wednesday, December 6, 2017 at 12:00 AM CET
261. pericentre shift and perturbation
Wednesday, November 29, 2017 at 12:00 AM CET
260. Maxwell-gravity
Wednesday, November 22, 2017 at 12:00 AM CET
259. wiggles in the metric
Wednesday, November 15, 2017 at 12:00 AM CET
258. gravitational wave receivers
Wednesday, November 8, 2017 at 12:00 AM CET
257. electromagnetic wave receivers
Wednesday, November 1, 2017 at 12:00 AM CET
256. naive relativity
Wednesday, October 25, 2017 at 12:00 AM CEST
255. wave interferometers
Wednesday, October 18, 2017 at 12:00 AM CEST
254. black hole growth
Wednesday, October 11, 2017 at 12:00 AM CEST
253. locally flat metric in cosmology
Wednesday, October 4, 2017 at 12:00 AM CEST
252. CQW holiday project: ocean level around Greenland
Wednesday, July 26, 2017 at 12:00 AM CEST
251. horizons in relativity
Wednesday, July 19, 2017 at 12:00 AM CEST
250. tidal shear invariants
Wednesday, July 12, 2017 at 12:00 AM CEST
249. clocks in acceleration
Wednesday, July 5, 2017 at 12:00 AM CEST
248. 120 - gasp! gasp!
Wednesday, June 28, 2017 at 12:00 AM CEST
247. 120 - gasp!
Wednesday, June 21, 2017 at 12:00 AM CEST
246. magic of Pauli-matrices
Wednesday, June 14, 2017 at 12:00 AM CEST
245. Pauli and Euclid
Wednesday, June 7, 2017 at 12:00 AM CEST
244. Pauli and Lorentz
Wednesday, May 31, 2017 at 12:00 AM CEST
243. Pauli-decomposition
Wednesday, May 24, 2017 at 12:00 AM CEST
242. derivative of a constant
Wednesday, May 17, 2017 at 12:00 AM CEST
241. relativistic waves
Wednesday, May 10, 2017 at 12:00 AM CEST
240. Schwarzwald relativity
Wednesday, May 3, 2017 at 12:00 AM CEST
239. quantify curvature
Wednesday, April 26, 2017 at 12:00 AM CEST
238. duality and the propagation of waves
Sunday, April 23, 2017 at 10:41 AM CEST
237. dark energy in the lab
Wednesday, April 19, 2017 at 12:00 AM CEST
236. Rydberg satellites
Wednesday, April 12, 2017 at 12:00 AM CEST
235. entropy density
Wednesday, April 5, 2017 at 12:00 AM CEST
234. measurement of the Planck-constant
Wednesday, March 29, 2017 at 12:00 AM CEST
233. 40, 20, 10
Wednesday, March 22, 2017 at 12:00 AM CET
232. intuition from the geodesic equation
Wednesday, March 15, 2017 at 12:00 AM CET
231. Lorentz force and acceleration
Wednesday, March 8, 2017 at 12:00 AM CET
230. Christoffel-symbols and geodesic motion
Wednesday, March 1, 2017 at 12:00 AM CET
229. charge asymmetry, part 2
Wednesday, February 22, 2017 at 12:00 AM CET
228. gravitational field of the hot sun
Wednesday, February 15, 2017 at 12:00 AM CET
227. spin-down of the Crab-pulsar
Wednesday, February 8, 2017 at 12:00 AM CET
226. electromagnetic duality
Wednesday, February 1, 2017 at 12:00 AM CET
225. gravity and retardation
Wednesday, January 25, 2017 at 12:00 AM CET
224. forces in relativity
Saturday, January 21, 2017 at 7:07 PM CET
223. very heavy and very light
Wednesday, January 18, 2017 at 12:00 AM CET
222. forces on dust particles
Wednesday, January 11, 2017 at 12:00 AM CET
221. funny way of writing Maxwell's equations
Wednesday, January 4, 2017 at 12:00 AM CET
220. comets and their tails
Wednesday, December 21, 2016 at 12:00 AM CET
219. Poynting-flux and magnetic charges
Wednesday, December 14, 2016 at 12:00 AM CET
218. electrodynamics with non-conserved charges
Wednesday, December 7, 2016 at 12:00 AM CET
217. gravitational fields for non-conservative systems
Wednesday, November 30, 2016 at 12:00 AM CET
216. dark star
Wednesday, November 23, 2016 at 12:00 AM CET
215. dissipation time scale
Wednesday, November 16, 2016 at 12:00 AM CET
214. motion or not?
Wednesday, November 9, 2016 at 12:00 AM CET
213. implications of a confirmed Lambda
Tuesday, November 8, 2016 at 4:12 PM CET
212. cosmology works?
Wednesday, November 2, 2016 at 12:00 AM CET
211. spherical gravitational wave
Wednesday, October 26, 2016 at 12:00 AM CEST
210. electricity and gravity
Wednesday, October 19, 2016 at 12:00 AM CEST
209. CPT and relativity
Wednesday, October 12, 2016 at 12:00 AM CEST
208. solutions to general relativity
Wednesday, October 5, 2016 at 12:00 AM CEST
207. CQW holiday project: Oort's cloud
Wednesday, July 27, 2016 at 12:00 AM CEST
206. gravity from a variational principle
Wednesday, July 20, 2016 at 12:00 AM CEST
205. parity of gravitational fields
Wednesday, July 13, 2016 at 12:00 AM CEST
204. time reversal in Einstein's field equation
Wednesday, July 6, 2016 at 12:00 AM CEST
203. time- and spacelike vectors
Wednesday, June 29, 2016 at 1:00 AM CEST
202. similarity in cosmology
Wednesday, June 22, 2016 at 12:00 AM CEST
201. similarity in modern physics
Wednesday, June 15, 2016 at 12:00 AM CEST
200. local field equations and nonlocal components
Wednesday, June 8, 2016 at 12:00 AM CEST
199. homogeneity of random fields
Wednesday, June 1, 2016 at 12:00 AM CEST
198. equivalence between gravity and inertia
Wednesday, May 25, 2016 at 12:00 AM CEST
197. interstellar (the movie)
Wednesday, May 18, 2016 at 12:00 AM CEST
196. underdetermined electrodynamics?
Wednesday, May 11, 2016 at 12:00 AM CEST
195. underdetermined general relativity?
Wednesday, May 4, 2016 at 12:00 AM CEST
194. divergence-free tensors
Wednesday, April 27, 2016 at 12:00 AM CEST
193. eternal sunshine
Wednesday, April 20, 2016 at 12:00 AM CEST
192. more power, R2!
Wednesday, April 13, 2016 at 12:00 AM CEST
191. moonwalk
Wednesday, April 6, 2016 at 12:00 AM CEST
190. Zeno and cosmology
Wednesday, March 30, 2016 at 12:00 AM CEST
189. equivalence
Wednesday, March 23, 2016 at 12:00 AM CET
188. pi in the sky
Wednesday, March 16, 2016 at 12:00 AM CET
187. scale of homogeneity
Wednesday, March 9, 2016 at 12:00 AM CET
186. non-ideal fluids
Wednesday, March 2, 2016 at 12:00 AM CET
185. speed of light and speed of gravity
Wednesday, February 24, 2016 at 12:00 AM CET
184. negative cosmological constant
Wednesday, February 17, 2016 at 12:00 AM CET
183. curved or straight?
Wednesday, February 10, 2016 at 12:00 AM CET
182. correlation function
Wednesday, February 3, 2016 at 12:00 AM CET
181. Lorentz boosted resistor
Wednesday, January 27, 2016 at 12:00 AM CET
180. Lorentz boosted capacitor
Wednesday, January 20, 2016 at 12:00 AM CET
179. Lorentz boosted coil
Wednesday, January 13, 2016 at 12:00 AM CET
178. redshift drift
Wednesday, January 6, 2016 at 12:00 AM CET
177. Hubble-collapse
Wednesday, December 23, 2015 at 12:00 AM CET
176. Schwarzschild radius of electrons
Wednesday, December 16, 2015 at 12:00 AM CET
175. replacing Maxwell's equations
Wednesday, December 9, 2015 at 12:00 AM CET
174. gravitational wave interferometers
Wednesday, December 2, 2015 at 11:41 PM CET
173. Hubble nucleus
Wednesday, November 25, 2015 at 12:00 AM CET
172. let it rip!
Wednesday, November 18, 2015 at 12:00 AM CET
171. no big bang
Wednesday, November 11, 2015 at 12:00 AM CET
170. vacuum fluctuations
Wednesday, November 4, 2015 at 12:00 AM CET
169. conditions for cosmic horizons
Wednesday, October 28, 2015 at 12:00 AM CET
168. falling faster
Wednesday, October 21, 2015 at 12:00 AM CEST
167. cosmologies without beginning
Wednesday, October 14, 2015 at 12:00 AM CEST
166. gravity (the movie)
Wednesday, October 7, 2015 at 12:00 AM CEST
165. CQW holiday project: gravitational field of a cube
Wednesday, July 29, 2015 at 12:00 AM CEST
164. temperature measurement
Wednesday, July 22, 2015 at 12:00 AM CEST
163. wrong sign in the induction equation
Wednesday, July 15, 2015 at 12:00 AM CEST
162. magnetic charges and energy conservation
Wednesday, July 8, 2015 at 12:00 AM CEST
161. too many Maxwell equations?
Wednesday, July 1, 2015 at 12:00 AM CEST
160. critical density in stationary universes
Wednesday, June 24, 2015 at 12:00 AM CEST
159. conservation laws in relativity
Wednesday, June 17, 2015 at 12:00 AM CEST
158. Lambda in 2 dimensions
Wednesday, June 10, 2015 at 12:00 AM CEST
157. cosmology and chemistry
Wednesday, June 3, 2015 at 12:00 AM CEST
156. balance dark matter and dark energy
Wednesday, May 27, 2015 at 12:00 AM CEST
155. thermal vs. kinetic SZ-effect
Wednesday, May 20, 2015 at 12:00 AM CEST
154. mechanical similarity and the moon landing
Wednesday, May 13, 2015 at 12:00 AM CEST
153. FLRW-fluids
Wednesday, May 6, 2015 at 12:00 AM CEST
152. neutrinos everywhere!
Wednesday, April 29, 2015 at 12:00 AM CEST
151. Lenz-Runge-Laplace vector
Wednesday, April 22, 2015 at 12:00 AM CEST
150. cosmic acceleration maxed out
Wednesday, April 15, 2015 at 12:00 AM CEST
149. boosted electric and magnetic fields
Wednesday, April 8, 2015 at 12:00 AM CEST
148. Darwin-term in the Kepler-problem
Wednesday, April 1, 2015 at 12:00 AM CEST
147. constant radius of the Hubble sphere
Wednesday, March 25, 2015 at 12:00 AM CET
146. charge asymmetry
Wednesday, March 18, 2015 at 12:00 AM CET
145. mass content of the Universe
Wednesday, March 11, 2015 at 12:00 AM CET
144. oscillations in the expansion history
Wednesday, March 4, 2015 at 12:00 AM CET
143. recollapsing FLRW-universes
Wednesday, February 25, 2015 at 12:00 AM CET
142. just two equations?
Wednesday, February 18, 2015 at 12:00 AM CET
141. FLRW-universes with no big bang
Wednesday, February 11, 2015 at 12:00 AM CET
140. ambiguity in the Planck-units?
Wednesday, February 4, 2015 at 12:00 AM CET
139. cosmology in SI-units
Wednesday, January 28, 2015 at 12:00 AM CET
138. Einstein's grandfather clock
Wednesday, January 21, 2015 at 12:00 AM CET
137. fine structure for Keplerium
Wednesday, January 14, 2015 at 12:00 AM CET
136. inertial forces and mechanical work
Wednesday, December 17, 2014 at 12:00 AM CET
135. Eddington-limit for muons
Wednesday, December 10, 2014 at 12:00 AM CET
134. cosmic neutrinos in ICECUBE
Wednesday, December 3, 2014 at 12:00 AM CET
133. tidal stretching of Palomar 5
Wednesday, November 26, 2014 at 12:00 AM CET
132. a quantum of sunshine
Wednesday, November 19, 2014 at 12:00 AM CET
131. tidal forces in the gravity train
Wednesday, November 12, 2014 at 12:00 AM CET
130. anti-Earth
Wednesday, November 5, 2014 at 12:00 AM CET
129. correlation coefficient
Wednesday, October 29, 2014 at 12:00 AM CET
128. Eddington temperature
Wednesday, October 22, 2014 at 12:00 AM CEST
127. Boltzmann-tail of the Planck-spectrum
Wednesday, October 15, 2014 at 12:00 AM CEST
126. natural value of the Hubble constant
Wednesday, October 8, 2014 at 12:00 AM CEST
125. Boltzmann-photons
Wednesday, October 1, 2014 at 12:00 AM CEST
124. CQW holiday project: NFW-wave function
Wednesday, July 30, 2014 at 12:00 AM CEST
123. Roche limit for a drop of water
Wednesday, July 23, 2014 at 12:00 AM CEST
122. periapsis recession
Wednesday, July 16, 2014 at 12:00 AM CEST
121. units of spectra
Wednesday, July 9, 2014 at 12:00 AM CEST
120. a much smaller Planck-mass
Wednesday, July 2, 2014 at 12:00 AM CEST
119. Newton's Indian rope trick
Wednesday, June 25, 2014 at 12:00 AM CEST
118. asymptotic Hubble-function
Wednesday, June 18, 2014 at 12:00 AM CEST
117. cosmic Unruh-effect
Wednesday, June 11, 2014 at 12:00 AM CEST
116. Dirac's large numbers
Wednesday, June 4, 2014 at 12:00 AM CEST
115. temperature in a FLRW-universe
Wednesday, May 28, 2014 at 12:00 AM CEST
114. Sunyaev-Zel'dovich effects with neutrinos
Wednesday, May 21, 2014 at 12:00 AM CEST
113. cluster cooling by immersion into the CMB
Wednesday, May 14, 2014 at 12:00 AM CEST
112. boundary to quantum cosmology
Wednesday, May 7, 2014 at 12:00 AM CEST
111. coasting dark energy universe
Wednesday, April 30, 2014 at 12:00 AM CEST
110. Ricci-scalar in a FLRW-universe
Wednesday, April 23, 2014 at 12:00 AM CEST
109. Wien displacements in many dimensions
Wednesday, April 16, 2014 at 12:00 AM CEST
108. braking by scattering
Wednesday, April 9, 2014 at 12:00 AM CEST
107. Planck, Bose and Boltzmann
Wednesday, April 2, 2014 at 12:00 AM CEST
106. fundamentals of cosmology
Wednesday, March 26, 2014 at 12:00 AM CET
105. fat Hubble sphere
Wednesday, March 19, 2014 at 12:00 AM CET
104. astronomy units in cosmology
Wednesday, March 12, 2014 at 12:00 AM CET
103. axioms of Lagrangian mechanics
Wednesday, March 5, 2014 at 12:00 AM CET
102. quantum statistics
Wednesday, February 26, 2014 at 12:00 AM CET
101. cosmic slow-motion
Wednesday, February 19, 2014 at 12:00 AM CET
100. Eddington's number
Wednesday, February 12, 2014 at 12:00 AM CET
99. gravitational Rydberg constant
Wednesday, February 5, 2014 at 12:00 AM CET
98. magic of the Gaussian distribution
Wednesday, January 29, 2014 at 12:00 AM CET
97. relativistic natural system of units
Wednesday, January 22, 2014 at 12:00 AM CET
96. subway to New Zealand
Wednesday, January 15, 2014 at 12:00 AM CET
95. nucleosynthesis with unstable nuclei
Wednesday, January 8, 2014 at 12:00 AM CET
94. island universe
Wednesday, December 18, 2013 at 12:00 AM CET
93. life in the early universe
Wednesday, December 11, 2013 at 12:00 AM CET
92. quantum microwave background
Wednesday, December 4, 2013 at 12:00 AM CET
91. classical photons
Wednesday, November 27, 2013 at 12:00 AM CET
90. radiation density
Wednesday, November 20, 2013 at 12:00 AM CET
89. slow acoustic waves
Wednesday, November 13, 2013 at 12:00 AM CET
88. natural scale of the Universe
Wednesday, November 6, 2013 at 12:00 AM CET
87. galaxy rotation curves at large radii
Wednesday, October 30, 2013 at 12:00 AM CET
86. cosmic neutrino background
Wednesday, October 23, 2013 at 12:00 AM CEST
85. shape of the Hubble-law
Wednesday, October 16, 2013 at 12:00 AM CEST
84. equation of state of baryons
Wednesday, October 9, 2013 at 12:00 AM CEST
83. thermal wavelength
Wednesday, October 2, 2013 at 12:00 AM CEST
82. Planck's summer: variations in \Lambda
Wednesday, August 7, 2013 at 12:00 AM CEST
81. Planck's summer: varying electron masses
Wednesday, July 31, 2013 at 12:00 AM CEST
80. Planck's summer: observation of the CNB
Wednesday, July 24, 2013 at 12:00 AM CEST
79. Planck's summer: gauge independence of cosmological surveys
Wednesday, July 17, 2013 at 12:00 AM CEST
78. Planck's summer: particle size matters!
Wednesday, July 10, 2013 at 12:00 AM CEST
77. Planck's summer: CMB observations without CMB photons
Wednesday, July 3, 2013 at 12:00 AM CEST
76. CMB as an ideal black body
Wednesday, June 26, 2013 at 12:00 AM CEST
75. CMB recombination
Wednesday, June 19, 2013 at 12:00 AM CEST
74. advection with the Hubble flow
Wednesday, June 12, 2013 at 12:00 AM CEST
73. supernovae at high redshift
Wednesday, June 5, 2013 at 12:00 AM CEST
72. dark energy takes over...
Wednesday, May 29, 2013 at 12:00 AM CEST
71. size of the Universe
Wednesday, May 22, 2013 at 12:00 AM CEST
70. tests for FLRW-cosmologies
Wednesday, May 15, 2013 at 12:00 AM CEST
69. energy input into the CMB
Wednesday, May 8, 2013 at 12:00 AM CEST
68. inflationary perturbations
Wednesday, May 1, 2013 at 12:00 AM CEST
67. invariants of the lensing Jacobian
Wednesday, April 24, 2013 at 12:00 AM CEST
66. Lambda as a source of energy
Wednesday, April 17, 2013 at 12:00 AM CEST
65. thermal equilibrium and the CMB
Wednesday, April 10, 2013 at 12:00 AM CEST
64. limitations of the NFW-profile shape
Wednesday, April 3, 2013 at 12:00 AM CEST
63. decaying vorticity
Wednesday, March 27, 2013 at 12:00 AM CET
62. Higgs mechanism
Wednesday, March 20, 2013 at 12:00 AM CET
61. electroweak phase transition
Wednesday, March 13, 2013 at 12:00 AM CET
60. thinking outside the box
Wednesday, March 6, 2013 at 12:00 AM CET
59. back to the future
Wednesday, February 27, 2013 at 12:00 AM CET
58. Hubble slow motion
Wednesday, February 20, 2013 at 12:00 AM CET
57. scale-invariance of perturbations
Wednesday, February 13, 2013 at 12:00 AM CET
56. cosmic conspiracy for rotation curves
Wednesday, February 6, 2013 at 12:00 AM CET
55. gravity in 2d and 3d
Wednesday, January 30, 2013 at 12:00 AM CET
54. homogeneous and anisotropic cosmology
Wednesday, January 23, 2013 at 12:00 AM CET
53. destruction of gravitationally bound systems
Wednesday, January 16, 2013 at 12:00 AM CET
52. conformal time in Lambda-driven expansion
Wednesday, January 9, 2013 at 12:00 AM CET
51. virial theorem in clusters
Wednesday, December 19, 2012 at 12:00 AM CET
50. peculiar motion and the CMB
Wednesday, December 12, 2012 at 12:00 AM CET
49. inflationary dynamics
Wednesday, December 5, 2012 at 12:00 AM CET
48. Hubble expansion and superluminality
Wednesday, November 28, 2012 at 12:00 AM CET
47. redundancy in the Friedmann equations
Wednesday, November 21, 2012 at 12:00 AM CET
46. mechanical similarity and planetary orbits
Wednesday, November 14, 2012 at 12:00 AM CET
45. cold core (aka cooling flow)
Wednesday, November 7, 2012 at 12:00 AM CET
44. gravitationally bound systems
Wednesday, October 31, 2012 at 12:00 AM CET
43. CMB and SNe
Wednesday, October 24, 2012 at 12:00 AM CEST
42. gravitational interaction of photons
Wednesday, October 17, 2012 at 12:00 AM CEST
41. dark energy equation of state
Wednesday, October 10, 2012 at 12:00 AM CEST
40. gravity and dimensionality
Wednesday, October 3, 2012 at 12:00 AM CEST
39. uncertainty and inflation
Wednesday, September 26, 2012 at 12:00 AM CEST
38. planetary atmospheres
Wednesday, September 19, 2012 at 12:00 AM CEST
37. Copernican principle
Wednesday, September 12, 2012 at 12:00 AM CEST
36. atmospheric pressure on Venus
Wednesday, September 5, 2012 at 12:00 AM CEST
35. Sunyaev-Zel'dovich effect
Wednesday, July 11, 2012 at 12:00 AM CEST
34. non-trivial topology of the Universe
Wednesday, July 4, 2012 at 12:00 AM CEST
33. baryonic acoustic oscillations
Wednesday, June 27, 2012 at 12:00 AM CEST
32. haloes of all sizes
Wednesday, June 20, 2012 at 12:00 AM CEST
31. static universe
Wednesday, June 13, 2012 at 12:00 AM CEST
30. gravitational lensing
Wednesday, June 6, 2012 at 12:00 AM CEST
29. black body in 4 dimensions
Wednesday, May 30, 2012 at 12:00 AM CEST
28. selection bias - cosmo CSI
Wednesday, May 23, 2012 at 12:00 AM CEST
27. time-variation of the CMB
Wednesday, May 16, 2012 at 12:00 AM CEST
26. CDM particle properties
Thursday, May 10, 2012 at 12:00 AM CEST
25. negative redshifts
Thursday, May 3, 2012 at 12:00 AM CEST
24. fine structure constant
Thursday, April 26, 2012 at 12:00 AM CEST
23. Olbers' paradoxon
Thursday, April 19, 2012 at 12:00 AM CEST
22. to infinity and beyond...
Thursday, April 12, 2012 at 12:24 AM CEST
21. CMB dipole - fact or fiction?
Wednesday, April 11, 2012 at 11:04 PM CEST
20. digits in physical constants
Thursday, April 5, 2012 at 1:00 AM CEST
19. CMB temperature
Thursday, March 29, 2012 at 1:00 AM CEST
18. age of the Universe
Thursday, March 22, 2012 at 1:00 AM CET
17. time-dependence of cosmological constants
Thursday, March 15, 2012 at 1:00 AM CET
16. Mercury's orbit
Wednesday, March 14, 2012 at 1:00 AM CET
15. precision cosmology
Wednesday, March 7, 2012 at 11:01 PM CET
14. lensing on an expanding metric
Thursday, March 1, 2012 at 12:14 AM CET
13. Minkowski metric
Saturday, February 25, 2012 at 1:21 PM CET
12. voids
Monday, February 20, 2012 at 8:07 PM CET
11. Schwarzschild radius
Friday, February 17, 2012 at 7:46 PM CET
10. distance measures
Friday, February 10, 2012 at 10:23 AM CET
9. Gaussianity
Friday, February 3, 2012 at 10:25 AM CET
8. redshift space
Friday, January 27, 2012 at 10:26 AM CET
7. SZ-effect
Friday, January 20, 2012 at 10:26 AM CET
6. dark energy
Friday, January 13, 2012 at 10:27 AM CET
5. Hubble function
Friday, January 6, 2012 at 10:27 AM CET
4. nucleosynthesis
Friday, December 30, 2011 at 10:28 AM CET
3. coldest place
Friday, December 23, 2011 at 10:29 AM CET
2. distances
Friday, December 16, 2011 at 10:29 AM CET
1. change of redshift
Friday, December 9, 2011 at 10:30 AM CET