I'm simply paraphrasing Ricardo's law of rent. It's pretty straightforward microeconomics.

Worst rent free location just refers to the next-best-alternative, so yes, homelessness, or subsistence farming in a marginal location, etc.

Both demand and supply straightforwardly affect housing rent; it is not just "productivity" that determines what the cost of physically residing in a certain area will be. For example, if a different city close by suddenly becomes much more attractive, demand will (at least in the short-term) slightly go down in the initial city, which will push rent down a bit, even though the productivity in this city has stayed the same.

Sure, I already said housing is subject to supply and demand.

Even in a hypothetical word that looked like ours except there was no technological improvement, rents would still change over time because of demand & supply factors, governmental regulation and deregulation, etc. 

Obviously true. And?

If we give all renters in a city $10k (say, by a tax cut, which is mostly functionally equivalent to UBI anyway, at least for our purposes here), are you predicting that this will not actually result in them retaining more dollars in their pockets after paying rent to their landlords?

Landlords will raise prices until the value of living in that city with $10k tax cut = the value of living in the next city with no tax cut, modulo friction. People will want to move into the tax cut city, raising rents.

Local cafes, bakeries and hair salons etc. will raise their prices a commensurate amount, and the improved "productivity" of these local businesses will result in an increase in competition for those locations, raising rents for businesses as well. 

The nominal incomes of renters and local business owners increase, but in the end the rentiers benefit. 

The income and substitution effects can't fully negate all increases in income, otherwise billionaires couldn't exist, and everyone would live paycheck to paycheck. 

Housing supply is elastic, land supply is not. Rent from "house-owner" to renter may have a functioning supply curve, but ground rent sucks up all UBI due to its perfectly inelastic supply curve.

QoL has of course risen despite this, because rent can only demand the different between the worst available rent-free location and the location at hand -- as technology improves, the productivity at the worst rent-free location (the margin of production) rises, and what people get to keep post-rent rises. 

UBI is simply a handout to rentiers.  Progress that improves the margin of production raises the floor of poverty. 

These listings don't clearly list fresnel lens as a feature / component, did you order yourself to confirm? And can you advise on the best search terms?

This was truly elucidating for a cis male with evidently low openness. I've long experienced cognitive dissonance between my purported liberalism wrt what people do to their own bodies and the offense I took toward gender identity and early medical/surgical interventions. Due to the cognitive dissonance, I've avoided honest deep dives into the topic, and this was a great introduction to a thesis that I could actually swallow. 

Thanks for taking the time to read.

Here's a 4 time board certified MD's primer on light that mentions the paper (and related research): 

Other highlights:

• Sun exposure decreases all cause mortality, including from melanoma
• Sun exposure has beneficial effect on brain volume in multiple sclerosis, independent of consequent vit D

As your background is in optics, can I get your opinion on this paper on the intersection of indoor lighting, optics and our responses to light wavelengths, and public health: https://www.melatonin-research.net/index.php/MR/article/view/19

To me it's on the knife's edge separating woo and legitimate niche research, I would like an educated opinion.