Surat Al-‘An`ām (The Cattle) – سورة الأنعام
السَّمَاوَاتِ وَالْأَرْضَ بِالْحَقِّ ۖ وَيَوْمَ يَقُولُ كُن فَيَكُونُ ۚ قَوْلُهُ الْحَقُّ ۚ وَلَهُ الْمُلْكُ يَوْمَ يُنفَخُ فِي الصُّورِ ۚ عَالِمُ الْغَيْبِ وَالشَّهَادَةِ ۚ وَهُوَ الْحَكِيمُ الْخَبِيرُ
It is He (God) who created the heavens and the earth in true (proportions): the day He said, “Be,” behold! it is. His word is the truth. His will be the dominion the day the trumpet will be blown. He knows the unseen as well as that which is open. For He is the Wise, well acquainted (with all things) | QS 6:73
That would lead to strange effects in some parts of the universe, where time and light would be so curved that you could see the back of your own head. Also, a long-held theory about the universe — that it looks much the same anywhere — would have to be abandoned. And finally, the universe would be finite, rather than extending in every direction forever (end of time).
Surat Az-Zumar (The Troops) – سورة الزمر
وَنُفِخَ فِي الصُّورِ فَصَعِقَ مَن فِي السَّمَاوَاتِ وَمَن فِي الْأَرْضِ إِلَّا مَن شَاءَ اللَّهُ ۖ ثُمَّ نُفِخَ فِيهِ أُخْرَىٰ فَإِذَا هُمْ قِيَامٌ يَنظُرُونَ
And the Horn will be blown, and whoever is in the heavens and whoever is on the earth will fall dead except whom Allah wills. Then it will be blown again, and at once they will be standing, looking on. | QS 39:68
The new shape, predicted by careful mathematical modeling to fit with known astronomical data, would have the universe stretched out into a long funnel, flaring into a bell-like shape at one end. The thin end would be infinitely long — but so narrow that it would have a finite volume.
The “bell” of the trumpet would also be peculiar: it would flare out, but a spaceship that could somehow navigate towards the open end would eventually find itself flying back along the “outside surface” of the bell.
The “space” in any small part of the “horn” is saddle-shaped, like a Pringles potato crisp. Such a “negatively curved” space would act as a warped lens, distorting the image around the blobs so they look elliptical to astronomers.
Another property of a “trumpet” universe would be that large blobs more than about 60 degrees across would be absent. So far, scientists have also found this to be the case.
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