Did the Buddha discover jhana by himself?

There are many kinds of samadhi.Jhana is Right Samadhi.The one taught by Siddharta's teachers were not what The Buddha called Right Samadhi. Right Samadhi which is Jhana can only be achieved if one has Right View.Different kind of samadhi can produce rapture bliss calm.But are not Jhana without Right View.Samatha meditation shouldn't be discouraged as it is a part of the Eight Noble Path.Siddharta remembered The First Jhana when he was meditating under extreme conditions.So he could not have been practicing Right Samadhi Jhana at that point.But he was definitely practicing deep samadhi as an astetic.

Prior to the Buddha there were practitioners who practiced higher absolutions. Buddha's contribution was the practice of the right concentration. The right concentration is the concentration while being aware of the reality, i.e., arising and passing of phenomena and characteristics of the phenomena. (Different people and lineages may interpret right concentration differently.)

If Jhana is taken or interpreted in the context of the right type of concentration then it will exclude any other form of absorptions based concentration.

Well-researched question but I find it silly nonetheless. Something like concentration attainment is the cause of everything holistic we have today: acupuncture, chi gong, kundalini activation, etc.

"Jhana practice" = centering oneself on blissful state

• ther are myriad, infinite ways to achieve this. My teacher said even scratching your ear is a type of jhana!
• i've read many accounts of the Buddha leaving home and learning from many yogis, many of whom manifested the blisses and powers of dhyana.
• the buddha also spontaneously entered dhyana on his own as a child

vipassana = practicing pure, naked awareness

• a crucial practice for self-awakening but is learning to be pure and nakedly aware really a buddhist invention? can buddhism or anything own being purely aware of the present moment?

These are fundamental practices for not just humans but any being.

Alexander Wynne published a book on history of meditation [1]. On the subject of jhana, he points that a description of the first jhana appears in a Mahābhārata passage "where it is said that for the sage who has the first dhyāna, there is vicāra, vitarka and viveka" -- no descriptions of further jhanas seem to appear.

He argues that it is likely that this passage was borrowed from Buddhism -- and overall, that it is likely there was interchange of knowledge of meditation between both traditions.

Maybe the formula and attainment of 1st jhana were known to ascetics in general. Maybe they could attain it, but had not systematize it (with it's factors and hindrances) and later borrowed the formula from the Buddha. Or maybe the Buddha came up with it on his own. If we trust the reading of the suttas where the Buddha remembers an early experience of jhana, and that this meant no contemporary teacher knew how to attain it, the later might be true.

Now, on formless meditation, Alexander concludes that (paraphrasing):

• The buddhist list of four formless spheres was inherited from Alara Kalama and Uddakha Ramaputta.
• Formless meditation is related to element meditation
• Therefore element meditation was borrowed from the same non-Buddhist source as was formless meditation (eg. from the two teachers)
• The doctrinal background of element meditation and formless meditation is provided by a list of six dhatu
• The list is based on early Brahminic cosmogonies
• Brahminic cosmogonies provide the doctrinal background to meditation in early Brahmanism
• Therefore, element meditation and formless meditation were borrowed from a brahmanic source
• The brahmanic source is probably these former teachers (Alara Kalama and Uddakha Ramaputta, Alara Kalama and Rāma, or perhaps the three?).

It might be worth to mention that the first ascetics the Buddha considered teaching after attaining nibbāna were Alara and Uddakha, for they had "little dust in their eyes" [2].

[1] The Origin of Buddhist Meditation, 2007

[2] Ariyapariyesana Sutta

I quote an excerpt of this answer from Ven. Yuttadhammo. You may read the answer for details.

The orthodox view is that samatha meditation was not discovered by the Buddha and vipassana meditation was.

The orthodox view is that the Bodhisatta cultivated samatha meditation countless times in his past lives before finally discovering vipassana.