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Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

Registrationplugin-autotooltip__plain plugin-autotooltip_bigRegistration

At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

After you've registered, you'll be able to login with your password at any time…

How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

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Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax? A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual …

Newsplugin-autotooltip__plain plugin-autotooltip_bigNews

[ newest at the top ]

• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn th…

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Legalplugin-autotooltip__plain plugin-autotooltip_bigLegal

Content in general

Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…


541 unknowns listed

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Wikenigma - an Encyclopaedia of Unknowns Wikenigma - an Encyclopaedia of the Unknown Science

Expansion of the universe

Note: This item is one of a special case - Known Unknowables

Current cosmological theory, backed up by many diverse observations, suggests that the universe is not only expanding, but that the speed of expansion is accelerating over time. Thus the limit of the observable universe is not only receding away from us (and from every other location in the universe) but the speed at which it recedes is increasing. If current theory (and the observations which lead to it) are correct, the implication is that any parts of the universe which are beyond the visibility limit will always remain unknowable.

“Assuming dark energy remains constant (an unchanging cosmological constant), so that the expansion rate of the Universe continues to accelerate, there is a “future visibility limit” beyond which objects will never enter our observable universe at any time in the infinite future, because light emitted by objects outside that limit would never reach us.”
source: Wikipedia

Note: Figures for the rate of expansion - a.k.a. the Hubble Constant - are derived either from measurements of the Cosmic Background Radiation, or from data on supernovae. The figures currently vary by about 9% - which, for a physical constant, would normally be considered spectacularly inaccurate. (source: New Scientist, Volume 247, Issue 3292, 25 July 2020, Page 15)

As of 2019, a new, third, method of measuring the constant has been developed using the LIGO gravity-wave detector. The results are preliminary, and are still being compiled. See: arXiv org


Also see : Dark Energyplugin-autotooltip__plain plugin-autotooltip_bigDark Energy

"“The observational results of the latest 15 to 20 years have established a standard model for the cosmology which has some amazing consequences. A mysterious entity, the dark energy, has been confirmed as the dominant component of the Universe, and is als…

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